Copolymer, electroluminescence device material including copolymer, and electroluminescence device

ABSTRACT

A copolymer including a structural unit represented by Chemical Formula 1wherein the copolymer is capable of improving luminous efficiency and durability, particularly, an improvement in luminescence life-span, of an electroluminescence device, particularly a quantum dot electroluminescence device.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Japanese Patent Application No.2020-202696 filed in the Japan Patent Office on Dec. 7, 2020, and allthe benefits accruing therefrom under 35 U.S.C. § 119, the entirecontent of which is herein incorporated by reference.

BACKGROUND 1. Field

A copolymer, an electroluminescence device material including thecopolymer, and an electroluminescence device are disclosed.

2. Description of the Related Art

Research and development of electroluminescence devices (EL devices) areactively progressing. In particular, EL devices are expected to be usedas solid-light emitting type inexpensive and large area full colordisplay devices or recording light source arrays. An EL device is alight emitting device including a thin film of several nanometers toseveral hundred nanometers positioned between an anode and a cathode. Inaddition, the EL devices will usually include a hole transport layer, alight emitting layer, an electron transport layer, or the like.

The light emitting layer may include a fluorescent light emittingmaterial, e.g., a material that emits blue light, and a phosphorescentlight emitting material, e.g., a material that emits blue, green, or redlight. A phosphorescent light emitting material is a material whoseluminous efficiency is expected to be about 4 times that of afluorescent light emitting material. In addition, to best cover a widecolor gamut, Red-Green-Blue (RGB) light emitting materials will alsodemand an emission spectrum having a relatively narrow full width athalf maximum emission peak. Although fluorescent or phosphorescentemission materials that emit deep blue light are of interest, there areno currently available EL devices on the market with relatively longlife-span and that satisfy the viewpoint of color purity.

As a way of solving such a technical problem, light emitting devicesthat use “quantum dot” which is an inorganic light emitting material asa light emitting material (See, Patent Document 1, Japanese PatentLaid-Open Publication No. 2010-199067) have been developed. Quantum dots(QD) are semiconductor materials having crystal structures of severalnanometers in size. Because quantum dots are very small in size, asurface area per unit volume is large, and therefore, the nanocrystalsexhibit quantum confinement effects.

Due to the quantum confinement effect, a quantum dot is able to adjustthe emission wavelength by adjusting its size, and has are known to havecharacteristics such as improved color purity and high photoluminescence(PL) efficiency. A quantum dot electroluminescence device (QD LED) is athree-layered device including a quantum dot emission layer positionedbetween a hole transport layer (HTL) and an electron transport layer(ETL).

SUMMARY OF THE INVENTION

An embodiment provides a technology capable of improving the luminousefficiency and durability, e.g., improvement in luminescence life-span,of an electroluminescence device, e.g., a quantum dotelectroluminescence device.

An embodiment provides a polymer compound having a specific structure.

An embodiment provides a copolymer having a structural unit representedby Chemical Formula 1.

In Chemical Formula 1,

X is a single bond, -L_(1a)-, or -L_(1b)-L_(1c)-, wherein L_(1a),L_(1b), and L_(1c) are each independently a substituted or unsubstituteddivalent aromatic hydrocarbon group having 6 to 25 carbon atoms,

L₂ is a substituted or unsubstituted aromatic hydrocarbon group having 6to 25 carbon atoms, or a substituted or unsubstituted aromaticheterocyclic group having 3 to 25 ring-member atoms,

Ar₁ and Ar₂ are each independently a substituted or unsubstitutedaromatic hydrocarbon group having 6 to 25 carbon atoms or a substitutedor unsubstituted aromatic heterocyclic group having 3 to 25 ring-memberatoms, and

Y is a substituted or unsubstituted divalent aromatic hydrocarbon grouphaving 6 to 60 carbon atoms, or a substituted or unsubstituted divalentaromatic heterocyclic group having 3 to 60 ring-member atoms,

wherein, L₂, Ar₁, and Ar₂ satisfy at least one of the followingConditions (i) or (ii):

(i) Ar₁ and Ar₂ are different groups; and

(ii) L₂ and Ar₁ join to form a ring.

In Chemical Formula 1, L₂, Ar₁, and Ar₂ may satisfy “Condition (i): Ar₁and Ar₂ are different groups”, and Ar₁ and Ar₂ may each independently bea group represented by Chemical Formula 2A, Chemical Formula 2B,Chemical Formula 2C, or Chemical Formula 2D:

wherein, in Chemical Formula 2A and Chemical Formula 2B

R₁ and R₂ may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms, an aromatic hydrocarbongroup having 6 to 14 carbon atoms, or an aromatic heterocyclic grouphaving 3 to 25 ring-member atoms,

a and b may each independently be an integer of 1 to 4, and

a link without * indicates a bond to the nitrogen of the arylamine sidechain of Chemical Formula 1,

wherein, in Chemical Formula 2C and Chemical Formula 2D,

Z₁ may be CR_(a)R_(b), NR_(c), O, S, Se, or Te, wherein R_(a), R_(b),and R_(c) may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms, an aromatic hydrocarbongroup having 6 to 14 carbon atoms, or an aromatic heterocyclic grouphaving 3 to 25 ring-member atoms, or R_(a) and R_(b) may be joined toprovide a spiro structure,

R₁, R₂, and R₃ may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms, an aromatic hydrocarbongroup having 6 to 14 carbon atoms, or an aromatic heterocyclic grouphaving 3 to 25 ring-member atoms,

a and b may each independently be an integer of 1 to 4, and

a link without * indicates a bond to the nitrogen of the arylamine sidechain of Chemical Formula 1.

In Chemical Formula 1, L₂, Ar₁, and Ar₂ may satisfy “Condition (i): Ar₁and Ar₂ are different groups”, and Ar₁ and Ar₂ may each independently bea group represented by Group 2:

wherein, in Group 2,

R may each independently be a hydrogen atom or a linear or branchedhydrocarbon group having 1 to 14 carbon atoms,

a link without * is a bond to the nitrogen of an arylamine side chain ofChemical Formula 1, and

a hydrogen atom of an aromatic ring of a Group 2 structure may beoptionally substituted by a linear or branched hydrocarbon group having1 to 14 carbon atoms.

In Chemical Formula 1, L₂ may be a group represented by Chemical Formula3A or Chemical Formula 3B:

wherein, in Chemical Formula 3A and Chemical Formula 3B,

R₁ and R₂ may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms, an aromatic hydrocarbongroup having 6 to 14 carbon atoms, or an aromatic heterocyclic grouphaving 3 to 25 ring-member atoms,

a and b may each independently be an integer of 1 to 4,

* may indicate a linking portion with the bridge nitrogen of the mainchain carbazole ring of Chemical Formula 1, and

a link without * may indicate a bond to the nitrogen of the arylamineside chain of Chemical Formula 1.

In Chemical Formula 1, L₂ may be represented by Chemical Formula 3A-1 orChemical Formula 3B-1:

wherein, in Chemical Formula 3A-1 and Chemical Formula 3B-1,

R₁ and R₂ may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms, an aromatic hydrocarbongroup having 6 to 14 carbon atoms, or an aromatic heterocyclic grouphaving 3 to 25 ring-member atoms,

a and b may each independently be an integer of 1 to 4,

* may indicate a linking portion with the bridge nitrogen of the mainchain carbazole ring of Chemical Formula 1, and

a link without * may indicate a bond to the nitrogen of an arylamineside chain of Chemical Formula 1.

In Chemical Formula 1, L₂ may be a group represented by Group 3:

wherein, in Group 3,

* may indicate a linking portion with the bridge nitrogen of the mainchain carbazole ring of Chemical Formula 1,

a link without * indicates a bond to the nitrogen of the arylamine sidechain of Chemical Formula 1, and

a hydrogen atom of an aromatic ring of a Group 3 structure may beoptionally substituted by a linear or branched hydrocarbon group having1 to 14 carbon atoms.

In Chemical Formula 1, L₂, Ar₁, and Ar₂ may satisfy “Condition (ii), and

-L₂-N(Ar₁)(Ar₂) may be a group represented by Chemical Formula 4A orChemical Formula 4B:

wherein, in Chemical Formula 4A and Chemical Formula 4B,

R₁ and R₂ are each independently hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms, an aromatic hydrocarbongroup having 6 to 14 carbon atoms, or an aromatic heterocyclic grouphaving 3 to 25 ring-member atoms,

a and b are each independently an integer of 1 to 4,

* indicates a linking portion with the bridge nitrogen of the main chaincarbazole ring of Chemical Formula 1,

Cy is a substituted or unsubstituted N-containing heterocyclic ringgroup having 5 to 25 ring-member atoms, and

Ar₂ is defined as in Chemical Formula 1.

In Chemical Formula 1, L₂, Ar₁, and Ar₂ may satisfy Condition (ii), and

-L₂-N(Ar₁)(Ar₂) may be a group represented by Group 4:

wherein, in Group 4,

Ar₂ may be the same as in Chemical Formula 1,

* indicates a linking portion with the bridge nitrogen of the main chaincarbazole ring of Chemical Formula 1, and

a hydrogen atom of the aromatic ring of a Group 4 structure may beoptionally substituted by a linear or branched hydrocarbon group having1 to 14 carbon atoms.

In Chemical Formula 1, Ar₂ may be represented by one of Chemical Formula2A to Chemical Formula 2B:

wherein, in Chemical Formula 2A and Chemical Formula 2B

R₁ and R₂ may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms, an aromatic hydrocarbongroup having 6 to 14 carbon atoms, or an aromatic heterocyclic grouphaving 3 to 25 ring-member atoms,

a and b may each independently be an integer of 1 to 4, and

a link without * may indicate a bond to the nitrogen of an arylamineside chain of Chemical Formula 1,

wherein, in Chemical Formula 2C and Chemical Formula 2D,

Z₁ may be CR_(a)R_(b), NR_(c), O, S, Se, or Te, wherein R_(a), R_(b),and R_(c) may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms, an aromatic hydrocarbongroup having 6 to 14 carbon atoms, or an aromatic heterocyclic grouphaving 3 to 25 ring-member atoms, or R_(a) and R_(b) may be linked toeach other to provide a spiro structure,

R₁, R₂, and R₃ may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms, an aromatic hydrocarbongroup having 6 to 14 carbon atoms, or an aromatic heterocyclic grouphaving 3 to 25 ring-member atoms,

a and b may each independently be an integer of 1 to 4, and

a link without * may indicate a link to the nitrogen of the arylamineside chain of Chemical Formula 1.

In Chemical Formula 1, Ar₂ may be a group represented in Group 2:

wherein, in Group 2,

R may each independently be a hydrogen atom or a linear or branchedhydrocarbon group having 1 to 14 carbon atoms,

a link without * may indicate a bond to the nitrogen of the arylamineside chain of Chemical Formula 1, and

a hydrogen atom of an aromatic ring of a Group 2 structure may beoptionally substituted by a linear or branched hydrocarbon group having1 to 14 carbon atoms.

In Chemical Formula 1, Y may be represented by one of Chemical Formula5A to Chemical Formula 5E:

wherein, in Chemical Formula 5A

R₁ may each independently be hydrogen, a linear or branched hydrocarbongroup having 1 to 14 carbon atoms, an aromatic hydrocarbon group having6 to 14 carbon atoms, or an aromatic heterocyclic group having 3 to 25ring-member atoms,

a may be an integer of 1 to 4

wherein, in Chemical Formula 5B and Chemical Formula 5C,

Z₁ may be CR_(a)R_(b), NR_(c), O, S, Se, or Te, wherein R_(a), R_(b),and R_(c) may each independently be hydrogen, linear or branchedhydrocarbon group having 1 to 14 carbon atoms, an aromatic hydrocarbongroup having 6 to 14 carbon atoms, or an aromatic heterocyclic grouphaving 3 to 25 ring-member atoms, or R_(a) and R_(b) may be linked toeach other to provide a spiro structure,

R₁, R₂, R₃, and R₄ may each independently be hydrogen, a linear orbranched hydrocarbon group having 1 to 14 carbon atoms, an aromatichydrocarbon group having 6 to 14 carbon atoms, or an aromaticheterocyclic group having 3 to 25 ring-member atoms,

a and b may each independently be an integer of 1 to 3, and

c and d may each independently be an integer of 1 to 3,

wherein, in Chemical Formula 5D and Chemical Formula 5E

R₁, R₂, R₃, R₄, and R₅ may each independently be hydrogen, a linear orbranched hydrocarbon group having 1 to 14 carbon atoms, an aromatichydrocarbon group having 6 to 14 carbon atoms, or an aromaticheterocyclic group having 3 to 25 ring-member atoms, and

a, b, c, d, and e may each independently be an integer of 1 to 4.

In Chemical Formula 1, Y may be a group represented in Group 5:

wherein, in Group 5,

R₁, R₂, and R₄ may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms, a C6 to C28 aromatichydrocarbon group, or an aromatic heterocyclic group having 3 to 25ring-member atoms,

R₃ may each independently be hydrogen or a linear or branchedhydrocarbon group having 1 to 14 carbon atoms, and

a hydrogen atom of an aromatic ring of a Group 5 structure may beoptionally substituted by a linear or branched hydrocarbon group having1 to 14 carbon atoms.

In Chemical Formula 1, Y may be a group represented by at least one ofGroups (5-1) to (5-7).

According to another embodiment, a liquid composition includes theaforementioned copolymer and a solvent or a dispersive medium.

According to another embodiment, a thin film includes the aforementionedcopolymer.

According to another embodiment, an electroluminescence device materialincludes the aforementioned copolymer.

According to another embodiment, an electroluminescence device includesa first electrode and a second electrode, and at least one organic layerbetween the first electrode and the second electrode, wherein at leastone layer of the organic layer includes the aforementioned copolymer.

The organic layer including the copolymer may be a hole transport layeror a hole injection layer.

The organic layer may include a light emitting layer comprisingsemiconductor nanoparticles or an organometallic complex.

At least one layer of the organic layer may be formed by a coatingmethod.

An electroluminescence device, and in particular, a quantum dotelectroluminescence device having excellent luminous efficiency anddurability (particularly luminescence life-span), may be provided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view illustrating an electroluminescence deviceaccording to an embodiment.

FIG. 2 is a cross-sectional view showing the structure of a quantum dotused in examples.

DETAILED DESCRIPTION

In the electroluminescence device (especially a quantum dotelectroluminescence device) the hole transport material described inPatent Document 1, lacks the necessary luminous efficiency anddurability, i.e., a tested device lacks the necessary luminescencelife-span) for general applicability. To address such technicaldeficiencies in such a device we describe the following.

According to an embodiment, a copolymer having a structural unitrepresented by Chemical Formula 1 is provided:

In Chemical Formula 1,

X is a single bond, -L_(1a)-, or -L_(1b)-L_(1c)-, wherein, L_(1a),L_(1b), and L_(1c) are each independently a substituted or unsubstituteddivalent aromatic hydrocarbon group having 6 to 25 carbon atoms,

L₂ is a substituted or unsubstituted aromatic hydrocarbon group having 6to 25 carbon atoms, or a substituted or unsubstituted aromaticheterocyclic group having 3 to 25 ring-member atoms,

Ar₁ and Ar₂ are each independently a substituted or unsubstitutedaromatic hydrocarbon group having 6 to 25 carbon atoms or a substitutedor unsubstituted aromatic heterocyclic group having 3 to 25 ring-memberatoms,

Y is a substituted or unsubstituted divalent aromatic hydrocarbon grouphaving 6 to 60 carbon atoms, or a substituted or unsubstituted divalentaromatic heterocyclic group having 3 to 60 ring-member atoms,

wherein, L₂, Ar₁, and Ar₂ satisfy at least one of Conditions (i) or(ii):

-   -   (i) Ar₁ and Ar₂ are different groups; and    -   (ii) L₂ and Ar₁ join to form a ring.

As used herein, “structural unit represented by Chemical Formula 1” isalso referred to as “Structural Unit (1).”

A structural unit having a structure represented by Chemical Formula 1-1among “structural units represented by Chemical Formula 1” is alsoreferred to as “Structural Unit (1-1).”

A structural unit having a structure represented by Chemical Formula 1-2among “structural units represented by Chemical Formula 1” is alsoreferred to as “Structural Unit (1-2).”

—Y—  Chemical Formula 1-2

A copolymer having a structural unit represented by Chemical Formula 1is also referred to as a “copolymer.”

According to another embodiment, an electroluminescence device materialincludes the copolymer.

According to another embodiment, an electroluminescence device includesa first electrode and a second electrode facing each other, and anorganic layer including one or more layers disposed between the firstelectrode and the second electrode, wherein at least one of the organiclayers includes the aforementioned copolymer of Chemical Formula 1.

As used herein, the electroluminescence device is simply referred to as“LED.”

Quantum dot electroluminescence devices are also referred to simply as“QLEDs.”

An organic electroluminescence device is also simply referred to as“OLED.”

The light emitting layer or the carrier transport layer of theelectroluminescence device may be formed by using various low molecularmaterials or polymer materials. Among them, the low molecular materialsare excellent in terms of an efficiency life-span of the device.However, when such low molecular materials are used the device istypically manufactured using a high vacuum process, which will increasethe costs of production (manufacture).

For example, polymer materials, poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4′-(N-(4-sec-butyl phenyl)diphenyl amine)](TFB) and the like are known and widely accepted as a hole transportmaterial (for example, see, paragraph 0037 of Patent Document 1).However, these polymer materials may not have the desired long luminousefficiency and durability (luminescence life-span, see, ComparativeExample 1 described later). Accordingly, development of a polymermaterial capable of improving the luminous efficiency and/or durability(luminescence life-span) of a light emitting device is of great interestto those in the manufacture of displays.

The present inventors found that durability (luminescence life-span) maybe improved by applying the copolymer that includes Structural Unit(1-1) of Chemical Formula 1 in an electroluminescence device comparedwith known materials, e.g., hole transport materials. In addition, highluminous efficiency may be exhibited by applying the copolymer includingStructural Unit (1-1) of Chemical Formula 1 to an electroluminescencedevice.

A mechanism of exhibition of the efficacy by the aforementionedstructure is estimated as follows.

In the Structural Unit (1-1) of Chemical Formula 1, carbazole is presentin the main chain. Thereby, the HOMO level of the copolymer deepens, andluminous efficiency improves.

In the Structural Unit (1-1) of Chemical Formula 1, L₂, Ar₁, and Ar₂satisfy at least one of “Condition (i): Ar₁ and Ar₂ are differentgroups” or “Condition (ii): L₂ and Ar₁ join to form a ring”.

In other words, the side chain is identified as being an asymmetricamine. Accordingly, in the copolymer, molecular orbitals are delocalizednot only in the main chain but also in the side chain. As a result, itis believed that the rate of hole transport is increased, and durability(luminescence life-span) is improved.

More specifically, because a conventional polymer material typically hasinsufficient rates of hole transport, hole movement or transport in thematerial is slower than an electron transport in the material. As aresult, holes and electrons will likely combine primarily in a region ofa light emitting layer proximate to the hole transport layer side.Accordingly, the region of the light emitting layer proximate to thehole transport layer side may be more easily deteriorate or degrade,which results in poor durability (luminescence life-span) of the lightemitting device.

In contrast, the copolymer materials described herein will tend to havea rate of hole movement or transport and a rate of electron movement ortransport that is relatively more similar or equal to one another. As aresult, the emission region in a light emitting layer is expanded over alarger area. This in turn leads to the light emitting layer having lesslocal deterioration or local “high energetic” hot spots, and therefore,durability (luminescence life-span) may be improved.

Accordingly, an electroluminescence device (particularly, a quantum dotelectroluminescence device) including the copolymer having theStructural Unit (1-1) of Chemical Formula 1 may exhibit high luminousefficiency and simultaneously, improved durability (particularly, aluminescence life-span).

Moreover, since the copolymer has excellent a film-forming property andsolvent solubility, a film may be formed by a wet (coating) method.Therefore, by using the copolymer, the manufacture of light emittingpanels of a significantly larger area and high production efficiency ismade possible. The above effect may be effectively exhibited when thecopolymer is applied to an EL device, particularly a hole transportlayer or a hole injection layer of a QLED.

It is of course to be understood that the electronic mechanisms proposedby Applicant and described above is in practice in theory only, and thepresent disclosure and claims is not to be limited by the discussedproposed mechanisms.

Hereinafter, embodiments are described. The present disclosure is notlimited to the following embodiments. In addition, each drawing isexaggerated for better understanding and ease of description, and thedimensional ratio of each constituent element in each drawing may differfrom reality. In addition, when the embodiment of the present disclosurehas been described with reference to the drawings, the same referencenumerals are given to the same elements in the description of thedrawings, and redundant descriptions are omitted.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting. As used herein, thesingular forms “a,” “an,” and “the” are intended to include the pluralforms, including “at least one,” unless the content clearly indicatesotherwise. “At least one” is not to be construed as limiting “a” or“an.” “Or” means “and/or.” As used herein, the term “and/or” includesany and all combinations of one or more of the associated listed items.It will be further understood that the terms “comprises” and/or“comprising,” or “includes” and/or “including” when used in thisspecification, specify the presence of stated features, regions,integers, steps, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,regions, integers, steps, operations, elements, components, and/orgroups thereof.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this disclosure belongs. It willbe further understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art and thepresent disclosure, and will not be interpreted in an idealized oroverly formal sense unless expressly so defined herein. In the presentspecification, unless otherwise specified, operation and physicalproperties are measured under the conditions of room temperature (20° C.or more and 25° C. or less)/relative humidity 40% RH or more and 50% RHor less.

As used herein, unless otherwise specified, “substituted” refers tosubstitution with an alkyl group, a cycloalkyl group, a hydroxyalkylgroup, an alkoxyalkyl group, an alkoxyl group, a cycloalkoxyl group, analkenyl group, an alkynyl group, an amino group, an aryl group, anaryloxy group, an alkylthio group, a cycloalkylthio group, an arylthiogroup, an alkoxycarbonyl group, an aryloxycarbonyl group, a hydroxylgroup (—OH), a carboxyl group (—COOH), a thiol group (—SH), or a cyanogroup (—CN). Also, optionally the substituents are not same as thegroups being substituted. For example, an alkyl group is not substitutedwith an alkyl group.

Herein, the alkyl group as the substituent may be either a linear orbranched, and may be, for example a linear alkyl group having 1 to 20carbon atoms or a branched alkyl group having 3 to 20 carbon atoms.Specifically, the alkyl group may be a methyl group, an ethyl group, ann-propyl group, an isopropyl group, an n-butyl group, an isobutyl group,a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentylgroup, a tert-pentyl group, a neopentyl group, a 1,2-dimethylpropylgroup, an n-hexyl group, an isohexyl group, a 1,3-dimethylbutyl group, a1-isopropylpropyl group, a 1,2-dimethylbutyl group, an n-heptyl group, a1,4-dimethylpentyl group, a 3-ethylpentyl group, a2-methyl-1-isopropylpropyl group, a 1-ethyl-3-methylbutyl group, ann-octyl group, a 2-ethylhexyl group, a 3-methyl-1-isopropylbutyl group,a 2-methyl-1-isopropyl group, a 1-tert-butyl-2-methylpropyl group, ann-nonyl group, a 3,5,5-trimethylhexyl group, an n-decyl group, anisodecyl group, an n-undecyl group, a 1-methyldecyl group, an n-dodecylgroup, an n-tridecyl group, an n-tetradecyl group, an n-pentadecylgroup, an n-hexadecyl group, an n-heptadecyl group, an n-octadecylgroup, an n-nonadecyl group, an n-icosyl group, and the like.

As the substituent, the cycloalkyl group may include for example, acyclopropyl group, a cyclobutyl group, a cyclopentyl group, and acyclohexyl group.

As the hydroxyalkyl group, for example, the alkyl group may besubstituted with 1 to 3 (desirably, 1 or 2, and more particularly,desirably 1) hydroxy groups (for example, a hydroxymethyl group or ahydroxyethyl group).

As the alkoxyalkyl group, for example, the alkyl group may besubstituted with 1 to 3 (desirably 1 or 2 and more desirably 1) alkoxygroups.

As the substituent, the alkoxy group may be either linear or a branched,but desirably a linear alkoxy group having 1 to 20 carbon atoms or abranched chain alkoxy group having 3 to 20 carbon atoms. For example,the alkoxy group may be, for example, a methoxy group, an ethoxy group,a propoxy group, an isopropoxy group, a butoxy group, a pentyloxy group,a hexyloxy group, a heptyloxy group, a 3-ethylpentyloxy group anoctyloxy group, a 2-ethylhexyloxy group, a nonyloxy group, a decyloxygroup, an undecyloxy group, a dodecyloxy group, a tridecyloxy group, atetradecyloxy group, a pentadecyloxy group, a hexadecyloxy group, aheptadecyloxy group, an octadecyloxy group, and the like.

The cycloalkoxy group as a substituent may be, for example, acyclopropyloxy group, a cyclobutyloxy group, a cyclopentyloxy group, acyclohexyloxy group, and the like.

The alkenyl group may include, for example, a vinyl group, an allylgroup, a 1-propenyl group, an isopropenyl group, a 1-butenyl group, a2-butenyl group, a 3-butenyl group, a 1-pentenyl group, a 2-pentenylgroup, a 3-pentenyl group, a 1-hexenyl group, a 2-hexenyl group, a3-hexenyl group, a 1-heptenyl group, a 2-heptenyl group, a 5-heptenylgroup, a 1-octenyl group, a 3-octenyl group, a 5-octenyl group, and thelike.

The alkynyl group as a substituent may include, for example, anacetylenyl group, a 1-propynyl group, a 2-propynyl group, a 1-butynylgroup, a 2-butynyl group, a 3-butynyl group, a 1-pentynyl group, a2-pentynyl group, a 3-pentynyl group, 1-hexynyl group, a 2-hexynylgroup, a 3-hexynyl group, a 1-heptynyl group, a 2-heptynyl group, a5-heptynyl group, a 1-octynyl group, a 3-octynyl group, a 5-octynylgroup, and the like.

Examples of the aryl group as the substituent may include an aryl grouphaving 6 to 30 carbon atoms. The aryl group may include, for example, aphenyl group, a naphthyl group, a biphenyl group, a fluorenyl group, ananthryl group, a pyrenyl group, an azulenyl group, an acenaphthylenylgroup, a terphenyl group, and a phenanthryl group.

The aryloxy group as the substituent may include, for example, a phenoxygroup, and a naphthyloxy group.

The alkylthio group as the substituent may include, for example, amethylthio group, an ethylthio group, a propylthio group, a pentylthiogroup, a hexylthio group, an octylthio group, a dodecylthio group, andthe like.

The cycloalkylthio group as the substituent may include, for example, acyclopentylthio group and a cyclohexylthio group.

The arylthio group as the substituent may include, for example, aphenylthio group, a naphthylthio group, and the like.

The alkoxycarbonyl group as the substituent may include, for example, amethyloxy carbonyl group, an ethyloxy carbonyl group, a butyloxycarbonyl group, an octyloxy carbonyl group, a dodecyloxycarbonyl group,and the like.

The aryloxycarbonyl group as the substituent may include, for example, aphenyloxycarbonyl group, a naphthyloxycarbonyl group, and the like.

Copolymer

The copolymer according to an embodiment includes a structural unitrepresented by Chemical Formula 1 (Structural Unit (1)). The copolymerhaving the following structure includes Structural Unit (1-1). For thisreason, an electroluminescence device (particularly quantum dotelectroluminescence device) including the copolymer (especially in thehole transport layer) has excellent luminous efficiency and durability(long luminescence life-span). In addition, high current efficiencyand/or low driving voltage may also be achieved with the devicesdescribed herein.

The copolymer may include one type of structural unit (Structural Unit(1)) represented by Chemical Formula 1, or may include two or more typesof Structural Unit (1). The plurality of Structural Units (1) may existin a block type or in a random type.

In addition, when two or more types of Structural Units (1) are present,“Structural Unit (1-1)” of each Structural Unit (1) may be the same ordifferent. Similarly, when two or more types of Structural Units (1) arepresent, “Structural Units (1-2)” of each Structural Unit (1) may be thesame or different.

In Chemical Formula 1,

In Chemical Formula 1, L₂, Ar₁, and Ar₂ satisfy at least one of“Condition (i): Ar₁ and Ar₂ are different groups” and “Condition (ii):L₂ and Ar₁ form a ring with each other.”

X is a single bond, -L_(1a)-, or -L_(1b)-L_(1c)-, wherein L_(1a),L_(1b), and L_(1c) are each independently a substituted or unsubstituteddivalent aromatic hydrocarbon group having 6 to 25 carbon atoms. L_(1b)and L_(1c) may be the same or different. When a plurality of L_(1a)'s, aplurality of L_(1b)'s, and a plurality of L_(1c)'s are present, they maybe the same or different from each other. The substituted orunsubstituted divalent aromatic hydrocarbon group having 6 to 25 carbonatoms may be a substituted or unsubstituted C6 to C25 arylene group. Thesubstituted or unsubstituted divalent aromatic hydrocarbon group having6 to 25 carbon atoms is not particularly limited, but may be a divalentgroup derived from an aromatic hydrocarbon compound such as benzene(phenylene group), pentalene, indene, naphthalene, anthracene, azulene,heptalene, acenaphthene, phenalene, fluorene, phenanthrene, biphenyl,terphenyl, quaterphenyl, quinquephenyl, pyrene, 9,9-diphenyl fluorene,9,9′-spirobi[fluorene], 9,9-dialkyl fluorene, and the like. Further, thedivalent aromatic hydrocarbon group having 6 to 25 carbon atoms may be adivalent group derived from a structure in which two or more types ofthe aforementioned aromatic hydrocarbon compounds are combined, forexample by a single bond, a C1 to C6 alkylene group, or a heteroatomsuch as oxygen or sulfur.

For example, X may be a single bond or a divalent group (-L_(1a)- or-L_(1b)-L_(1c)-) derived from a compound such as benzene, fluorene,dibenzofuran, dibenzothiophene, or biphenyl. Specifically, X may be asingle bond and a divalent group (-L_(1a)- or -L_(1b)-L_(1c)-) derivedfrom a compound such as benzene (an o-, m-, or p-phenylene group),dibenzofuran, or fluorene. More specifically, X may be a single bond ora phenylene group (especially a p-phenylene group). In an embodiment, Xmay be a single bond. When X is as described above, the HOMO level ofthe copolymer may be appropriately controlled. In addition, a higherhole injection property, a higher triplet energy level, a lower drivevoltage, a film-forming property, or the balance of any two or more ofthese (particularly a hole injection property and a film-formingproperty) may also be achieved.

In an embodiment, L_(1a), L_(1b), and L_(1c) may be unsubstituted or anyone hydrogen atom may be replaced by a substituent. The number ofsubstituents introduced when any one of the hydrogen atoms in L_(1a),L_(1b), and L_(1c) is replaced is not particularly limited, but may be 1or more and 3 or less, for example 1 or more and 2 or less, orparticularly 1. When L_(1a), L_(1b), and L_(1c) have a substituent, thebonding position of the substituent is not particularly limited.

The substituent may be located as far from the nitrogen of the arylamineside chain to which X is linked via L₂ as possible. By the presence of asubstituent at this position, the HOMO level of the copolymer may beappropriately controlled. In addition, a higher hole injection property,a higher triplet energy level, a lower drive voltage, a film-formingproperty, or the balance of any two or more of these (particularly ahole injection property and a film-forming property) may be achieved.

L₂ is a substituted or unsubstituted aromatic hydrocarbon group having 6to 25 carbon atoms, or a substituted or unsubstituted aromaticheterocyclic group having 3 to 25 ring-member atoms. When a plurality ofL₂'s are present, they may be the same or different from each other.Examples of the aromatic hydrocarbon group having 6 to 25 carbon atomsmay be groups derived from the aromatic hydrocarbon compound in X(-L_(1a)- or -L_(1b)-L_(1c)-). The substituted or unsubstituted aromaticheterocyclic group having 3 to 25 ring-member atoms may be a substitutedor unsubstituted C2 to C25 heteroarylene group and may include at leastone, for example, 1 to 3 heteroatoms of N, O, S, Se, Te, Si, or P in thering. Examples of the aromatic heterocyclic group having 3 to 25ring-member atoms are not particularly limited, but may be specificallya group derived from heterocyclic aromatic compounds such as acridine,phenazine, benzoquinoline, benzoisoquinoline, phenanthridine,phenanthroline, anthraquinone, fluorenone, dibenzofuran, phenyldibenzofuran, dibenzothiophene, dibenzothiophene, carbazole, imidazophenanthridine, benzimidazophenanthridine, azadibenzofuran, 9-phenylcarbazole, azacarbazole, diazabenzothiophene, diazadibenzofuran,diazacarbazole, diazadibenzothiophene, xanthone, thioxanthone, pyridine,quinoline, anthraquinoline, and the like.

In addition, the aromatic hydrocarbon group having 6 to 25 carbon atomsand the aromatic heterocyclic group having 3 to 25 ring-member atoms maybe a group derived from a structure in which two or more types of thearomatic hydrocarbon compounds are combined as in X (-L_(1a)- or-L_(1b)-L_(1c)), or a group derived from a structure in which two ormore types of the heterocyclic aromatic compounds are combined, or agroup derived from a structure in which one or more type of the aromatichydrocarbon compound as in X (-L_(1a)- or -L_(1b)-L_(1c)-) and one ormore heterocyclic aromatic compounds are combined. Among them, the groupderived from the aromatic hydrocarbon compound or the aromaticheterocyclic ring group having 3 to 25 ring atoms may be a group derivedfrom a compound such as benzene (a phenylene group), biphenyl,terphenyl, quaterphenyl, fluorene, dibenzofuran or dibenzothiophene,desirably a group derived from benzene (phenylene group), biphenyl,fluorene or dibenzofuran, or more desirably a group derived from benzene(phenylene group) or biphenyl.

According to an embodiment, L₂ may be a group represented by ChemicalFormula 3A or Chemical Formula 3B.

In Chemical Formula 3A and Chemical Formula 3B,

R₁ and R₂ may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms (a C1 to C14 alkyl group,for example a C1 to C12 alkyl group, for example an n-octyl group, a2-ethylhexyl group, or an n-dodecyl group), an aromatic hydrocarbongroup having 6 to 14 carbon atoms (a C6 to C14 aryl group, for example aC6 to C10 aryl group), or an aromatic heterocyclic group having 3 to 25ring-member atoms (a C1 to C25 heteroaryl group, for example a C1 to C20heteroaryl group),

a and b may each independently be an integer of 1 to 4, and

* indicates a linking portion with the bridge nitrogen of the main chaincarbazole ring of Chemical Formula 1, and a link without * indicates abond to the nitrogen of the arylamine side chain of Chemical formula 1.

The group represented by Chemical Formula 3A and Chemical Formula 3B mayeach independently be a group represented by Chemical Formula 3A-1 andChemical Formula 3B-1, respectively.

In Chemical Formula 3A-1 and Chemical Formula 3B-1,

R₁ and R₂ may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms (a C1 to C14 alkyl group,for example, a C1 to C12 alkyl group, for example, an n-octyl group, a2-ethylhexyl group, or an n-dodecyl group), an aromatic hydrocarbongroup having 6 to 14 carbon atoms (a C6 to C14 aryl group, for example aC6 to C10 aryl group), or an aromatic heterocyclic group having 3 to 25ring-member atoms (a C1 to C25 heteroaryl group, for example a C1 to C20heteroaryl group or a C1 to C10 heteroaryl group),

a and b may each independently be an integer of 1 to 4, and

* indicates a linking portion with the bridge nitrogen of the main chaincarbazole ring of Chemical Formula 1, and a link without * indicates abond to the nitrogen of the arylamine side chain of Chemical formula 1.For example, L₂ may be a group represented by Group 3.

In Group 3,

* indicates a linking portion with the bridge nitrogen of the main chaincarbazole ring of Chemical Formula 1,

a link without * indicates a bond to the nitrogen of the arylamine sidechain of Chemical formula 1, and

a hydrogen atom of an aromatic ring of a Group 3 structure may beoptionally substituted by a linear or branched hydrocarbon group having1 to 14 carbon atoms.

In an embodiment, in Group 3, L₂ may be a moiety represented by (3-1),(3-4), or (3-13) to (3-24), or desirably a moiety represented by (3-4).Such group structures of L₂ may appropriately control the HOMO level ofthe copolymer. In addition, a higher hole injection property, a highertriplet energy level, a lower drive voltage, a film-forming property, orthe balance of any two or more of these (particularly a hole injectionproperty and a film-forming property) may be achieved. Moreover, whenL₂, Ar₁, and Ar₂ satisfy “Condition (ii): L₂ and Ar₁ join to form aring”, L₂ may be a trivalent group, and when Condition (ii) is notsatisfied, L₂ may be a divalent group.

Ar₁ and Ar₂ may each independently be a substituted or unsubstitutedaromatic hydrocarbon group having 6 to 25 carbon atoms, or a substitutedor unsubstituted aromatic heterocyclic group having 3 to 25 ring-memberatoms. When a plurality of Ar₁'s and Ar₂'s are present, they may be thesame or different from each other.

The aromatic hydrocarbon group having 6 to 25 carbon atoms and aromaticheterocyclic group having 3 to 25 ring-member atoms may be a groupderived from the aromatic hydrocarbon compound as in X (-L_(1a)- or-L_(1b)-L_(1c)-); a group derived from the heterocyclic aromaticcompound as in L₂; a group derived from a structure in which two or moretypes of the aromatic hydrocarbon compounds are combined as in X(-L_(1a)- or -L_(1b)-L_(1c)); a group derived from a structure in whichtwo or more types of heterocyclic aromatic compounds are combined as inL₂; or a group derived from a structure in which one or more types ofthe aromatic hydrocarbon compound as in X (-L_(1a)- or -L_(1b)-L_(1c)-)and the heterocyclic aromatic compound as in L₂.

Among them, the aromatic hydrocarbon group having 6 to 25 carbon atomsor the aromatic heterocyclic group having 3 to 25 ring-member atoms maybe a group derived from a compound such as benzene, biphenyl, fluorene,9,9-diphenyl fluorene, 9,9′-spirobi[fluorene], 9,9-dialkyl fluorene,dibenzofuran, phenyl dibenzofuran, dibenzothiophene, or phenyldibenzothiophene, desirably a group derived from a compound such asbenzene, biphenyl, fluorene, 9,9-diphenyl fluorene,9,9′-spirobi[fluorene], 9,9-dialkyl fluorene, dibenzofuran, or phenyldibenzofuran, or more desirably a group derived from a compound such asbenzene, biphenyl, 9,9-diphenyl fluorene, 9,9-dialkyl fluorene, ordibenzofuran.

The above structural groups of Ar₁ and Ar₂ may increase the rate of holemovement or transport within the copolymer, and thus may improvedurability (luminescence life-span) of a device. In addition, a higherhole injection property, a higher triplet energy level, a lower drivevoltage, a film-forming property, or the balance of any two or more ofthese (particularly a hole injection property and a film-formingproperty) may be achieved.

In an embodiment, Ar₂ may be a monovalent group. When L₂, Ar₁, and Ar₂satisfy “Condition (ii): L₂ and Ar₁ join to form a ring”, Ar₁ may be adivalent group, and when Condition (ii) is not satisfied, Ar₁ may be amonovalent group.

In an embodiment, L₂, Ar₁, and Ar₂ satisfy “Condition (i): Ar₁ and Ar₂are different groups,” and Ar₁ and Ar₂ may each independently be a grouprepresented by one of Chemical Formula 2A to Chemical Formula 2D.

In Chemical Formula 2A and Chemical Formula 2B,

R₁ and R₂ may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms (a C1 to C14 alkyl group,for example, a C1 to C12 alkyl group, for example, an n-octyl group, a2-ethylhexyl group, or an n-dodecyl group), an aromatic hydrocarbongroup having 6 to 14 carbon atoms (a C6 to C14 aryl group, for example aC6 to C10 aryl group), or an aromatic heterocyclic group having 3 to 25ring-member atoms (a C1 to C25 heteroaryl group, for example a C1 to C20heteroaryl group or a C1 to C10 heteroaryl group),

a and b may each independently be an integer of 1 to 4, and

a link without * indicates a bond to the nitrogen of the arylamine sidechain of Chemical Formula 1.

In Chemical Formula 2C and Chemical Formula 2D,

Z₁ may be CR_(a)R_(b), NR_(c), O, S, Se, or Te, wherein R_(a), R_(b),and R_(c) may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms (a C1 to C14 alkyl group,for example, a C1 to C12 alkyl group, for example, an n-octyl group, a2-ethylhexyl group, or an n-dodecyl group), an aromatic hydrocarbongroup having 6 to 14 carbon atoms (a C6 to C14 aryl group, for example aC6 to C10 aryl group), or an aromatic heterocyclic group having 3 to 25ring-member atoms (a C1 to C25 heteroaryl group, for example a C1 to C20heteroaryl group or a C1 to C10 heteroaryl group), or R_(a) and R_(b)may be linked to each other to provide a spiro structure (e.g.,fluorenyl group),

R₁, R₂, and R₃ may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms (a C1 to C14 alkyl group,for example, a C1 to C12 alkyl group, for example, an n-octyl group, a2-ethylhexyl group, or an n-dodecyl group), an aromatic hydrocarbongroup having 6 to 14 carbon atoms (a C6 to C14 aryl group, for example aC6 to C10 aryl group), or an aromatic heterocyclic group having 3 to 25ring-member atoms (a C1 to C25 heteroaryl group, for example a C1 to C20heteroaryl group or a C1 to C10 heteroaryl group),

a and b may each independently be an integer of 1 to 4, and

a link without * indicates a bond to the nitrogen of the arylamine sidechain of Chemical Formula 1.

For example, Ar₁ and Ar₂ may each independently be a group representedby Group 2.

In Group 2,

R may each independently be a hydrogen atom or a linear or branchedhydrocarbon group having 1 to 14 carbon atoms, and

a hydrogen atom of an aromatic ring of a Group 2 structure may beoptionally substituted by a linear or branched hydrocarbon group having1 to 14 carbon atoms.

The linear or branched hydrocarbon group having 1 to 14 carbon atoms maybe a C1 to C14 linear or branched alkyl group or C1 to C12 linear orbranched alkyl group; a C2 to C14 linear or branched alkenyl group or aC2 to C12 linear or branched alkenyl group; or a C2 to C14 linear orbranched alkynyl group or a C2 to C12 linear or branched alkynyl group,for example, a methyl group, an ethyl group, an n-propyl group, anisopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group,a tert-butyl group, an n-pentyl group, an isopentyl group, a tert-pentylgroup, a neopentyl group, a 1,2-dimethyl propyl group, an n-hexyl group,an isohexyl group, a 1,3-dimethylbutyl group, a 1-isopropyl propylgroup, a 1,2-dimethylbutyl group, an n-heptyl group, a 1,4-dimethylpentyl group, a 3-ethyl pentyl group, a 2-methyl-1-isopropyl propylgroup, a 1-ethyl-3-methyl butyl group, an n-octyl group, a 2-ethylhexylgroup, a 3-methyl-1-isopropyl butyl group, a 2-methyl-1-isopropyl group,a 1-tert-butyl-2-methyl propyl group, an n-nonyl group, a3,5,5-trimethyl hexyl group, an n-decyl group, an isodecyl group, ann-undecyl group, a 1-methyldecyl group, an n-dodecyl group, ann-tridecyl group, an n-tetradecyl group, a vinyl group, an allyl group,a 1-propenyl group, an isopropenyl group, a 1-butenyl group, a 2-butenylgroup, a 3-butenyl group, a 1-pentenyl group, a 2-pentenyl group, a3-pentenyl group, a 1-hexenyl group, a 2-hexenyl group, a 3-hexenylgroup, a 1-heptenyl group, a 2-heptenyl group, a 5-heptenyl group, a1-octenyl group, a 3-octenyl group, a 5-octenyl group, an acetylenylgroup, a 1-propynyl group, a 2-propynyl group, a 1-butynyl group, a2-butynyl group, a 3-butynyl group, a 1-pentynyl group, a 2-pentynylgroup, a 3-pentynyl group, 1-hexynyl group, a 2-hexynyl group, a3-hexynyl group, a 1-heptynyl group, a 2-heptynyl group, a 5-heptynylgroup, a 1-octynyl group, a 3-octynyl group, a 5-octynyl group, and thelike.

In an embodiment, Ar₁ and Ar₂ may be desirably a moiety represented byone of (2-1) to (2-24), or more desirably a moiety represented by one of(2-1) to (2-4), (2-16), (2-23), and (2-27). For example, the combinationof Ar₁ and Ar₂ may be a combination of (2-2) and (2-23), a combinationof (2-3) and (2-23), a combination of (2-4) and (2-23), a combination of(2-16) and (2-27), or a combination of (2-23) and (2-27).

In Group 2, R may be each independently a linear or branched (saturated)hydrocarbon group having 1 to 14 carbon atoms, desirably a linear orbranched (saturated) hydrocarbon group having 1 to 8 carbon atoms, ormore desirably a methyl group, an ethyl group, an n-propyl group, anisopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group,a tert-butyl group, an n-pentyl group, an isopentyl group, a tert-pentylgroup, a neopentyl group, a 1,2-dimethylpropyl group, an n-hexyl group,an isohexyl group, a 1,3-dimethylbutyl group, a 1-isopropylpropyl group,or a 1,2-dimethylbutyl group.

These Ar₁ and Ar₂ groups may increase the rate of hole movement ortransport within the copolymer, and thus may improve durability(luminescence life-span) of a device. In addition, a higher holeinjection property, a higher triplet energy level, a lower drivevoltage, a film-forming property, or the balance of any two or more ofthese (particularly a hole injection property and a film-formingproperty) may be achieved.

In an embodiment, when L₂, Ar₁, and Ar₂ satisfy “Condition (ii): L₂ andAr₁ join to form a ring”, -L₂-N(Ar₁)(Ar₂) may be a group represented byChemical Formula 4A or Chemical Formula 4B.

In Chemical Formula 4A and Chemical Formula 4B,

R₁ and R₂ may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms (a C1 to C14 alkyl group,for example, a C1 to C12 alkyl group, for example, an n-octyl group, a2-ethylhexyl group, or an n-dodecyl group), an aromatic hydrocarbongroup having 6 to 14 carbon atoms (a C6 to C14 aryl group, for example aC6 to C10 aryl group), or an aromatic heterocyclic group having 3 to 25ring-member atoms (a C1 to C25 heteroaryl group, for example a C1 to C20heteroaryl group or a C1 to C10 heteroaryl group),

a and b may each independently be an integer of 1 to 4,

* indicates a linking portion with the bridge nitrogen of the main chaincarbazole ring,

Cy may be a substituted or unsubstituted N-containing heterocyclic ringgroup having 5 to 25 ring-member atoms, and

Ar₂ is as defined in Chemical Formula 1.

The N-containing heterocyclic ring group having 5 to 25 ring-memberatoms may be a group derived from a heterocyclic compound that can be asubstituted or unsubstituted pyrrolidine, a substituted or unsubstitutedpyrazolidine, a substituted or unsubstituted piperidine, a substitutedor unsubstituted indoline, a substituted or unsubstituted piperazine, asubstituted or unsubstituted morpholine, a substituted or unsubstitutedthiazine, or a substituted or unsubstituted naphthyridine, or the like.

In an embodiment, when L₂, Ar₁, and Ar₂ satisfy “Condition (ii): L₂ andAr₁ join to form a ring”, -L₂-N(Ar₁)(Ar₂) may be a group represented byGroup 4.

In Group 4,

Ar₂ is as defined in Chemical Formula 1, and

a hydrogen atom of an aromatic ring of a Group 4 structure may beoptionally substituted by a linear or branched hydrocarbon group having1 to 14 carbon atoms.

In Group 4, the linear or branched hydrocarbon group having 1 to 14carbon atoms may be a C1 to C14 linear or branched alkyl group or C1 toC12 linear or branched alkyl group; a C2 to C14 linear or branchedalkenyl group or a C2 to C12 linear or branched alkenyl group; or a C2to C14 linear or branched alkynyl group or a C2 to C12 linear orbranched alkynyl group, for example, a methyl group, an ethyl group, ann-propyl group, an isopropyl group, an n-butyl group, an isobutyl group,a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentylgroup, a tert-pentyl group, a neopentyl group, a 1,2-dimethyl propylgroup, an n-hexyl group, an isohexyl group, a 1,3-dimethylbutyl group, a1-isopropyl propyl group, a 1,2-dimethylbutyl group, an n-heptyl group,a 1,4-dimethyl pentyl group, a 3-ethyl pentyl group, a2-methyl-1-isopropyl propyl group, a 1-ethyl-3-methyl butyl group, ann-octyl group, a 2-ethylhexyl group, a 3-methyl-1-isopropyl butyl group,a 2-methyl-1-isopropyl group, a 1-tert-butyl-2-methyl propyl group, ann-nonyl group, a 3,5,5-trimethyl hexyl group, an n-decyl group, anisodecyl group, an n-undecyl group, a 1-methyldecyl group, an n-dodecylgroup, an n-tridecyl group, an n-tetradecyl group, a vinyl group, anallyl group, a 1-propenyl group, an isopropenyl group, a 1-butenylgroup, a 2-butenyl group, a 3-butenyl group, a 1-pentenyl group, a2-pentenyl group, a 3-pentenyl group, a 1-hexenyl group, a 2-hexenylgroup, a 3-hexenyl group, a 1-heptenyl group, a 2-heptenyl group, a5-heptenyl group, a 1-octenyl group, a 3-octenyl group, a 5-octenylgroup, an acetylenyl group, a 1-propynyl group, a 2-propynyl group, a1-butynyl group, a 2-butynyl group, a 3-butynyl group, a 1-pentynylgroup, a 2-pentynyl group, a 3-pentynyl group, 1-hexynyl group, a2-hexynyl group, a 3-hexynyl group, a 1-heptynyl group, a 2-heptynylgroup, a 5-heptynyl group, a 1-octynyl group, a 3-octynyl group, a5-octynyl group, and the like.

In an embodiment, -L₂-N(Ar₁)(Ar₂) may be a moiety represented by (4-1),(4-4), or (4-7), or desirably a moiety represented by (4-4).

Ar₂ in -L₂-N(Ar₁)(Ar₂) may be a group represented by one of ChemicalFormula 2A to Chemical Formula 2D, and specifically, Ar₂ may be a groupas represented in Group 2.

The -L₂-N(Ar₁)(Ar₂) may increase the rate of hole movement or transportwithin the copolymer, and thus may improve durability (luminescencelife-span) of a device. In addition, a higher hole injection property, ahigher triplet energy level, a lower drive voltage, a film-formingproperty, or the balance of any two or more of these (particularly ahole injection property and a film-forming property) may be achieved.

In Chemical Formula 1, Y is a substituted or unsubstituted divalentaromatic hydrocarbon group having 6 to 60 carbon atoms, or a substitutedor unsubstituted divalent aromatic heterocyclic group having 3 to 60ring-member atoms.

The divalent aromatic hydrocarbon group having 6 to 60 carbon atoms maybe a C6 to C60 (e.g., C6 to C50, C6 to C40, C6 to C30, or C6 to C25)aryl group and the divalent aromatic heterocyclic group having 3 to 60ring-member atoms may be a C2 to C60 (e.g., C2 to C50, C2 to C40, C2 toC30, or C2 to C25) heteroaryl group and may include at least one, forexample, 1 to 3 heteroatoms such as N, O, S, Se, Te, Si, and P in thering. The divalent aromatic hydrocarbon group having 6 to 60 carbonatoms and the divalent aromatic heterocyclic group having 3 to 60ring-member atoms may be may be a divalent group derived from thearomatic hydrocarbon compound as in X (-L_(1a)- or -L_(1b)-L_(1c)-), adivalent group derived from the heterocyclic aromatic compound as in L₂,a divalent group derived from a structure in which two or more types ofthe aromatic hydrocarbon compounds are combined as in X (-L_(1a)- or-L_(1b)-L_(1c)), a divalent group derived from a structure in which twoor more types of heterocyclic aromatic compounds are combined as in L₂,or a divalent group derived from a structure in which one or more typesof the aromatic hydrocarbon compound as in X (-L_(1a)- or-L_(1b)-L_(1c)-) and the heterocyclic aromatic compound as in L₂.

Among them, the divalent aromatic hydrocarbon group having 6 to 25carbon atoms or the divalent aromatic heterocyclic group having 3 to 25ring-member atoms may be desirable; a divalent group derived from acompound such as benzene (a phenylene group), biphenyl, terphenyl,quaterphenyl, fluorene, dibenzofuran, or dibenzothiophene or a structurein which these compounds are combined may be more desirable; and adivalent group derived from benzene (a phenylene group), fluorene, ordibenzofuran, or a structure in which these compounds are combined maybe even more desirable.

A selection of Y may appropriately control the HOMO level of thecopolymer. In addition, a higher hole injection property, a highertriplet energy level, a lower drive voltage, a film-forming property, orthe balance of any two or more of these (particularly a hole injectionproperty and a film-forming property) may be achieved.

In an embodiment, Y may be a group represented by Chemical Formula 5A toChemical Formula 5E.

In Chemical Formula 5A

R₁ may each independently be hydrogen, a linear or branched hydrocarbongroup having 1 to 14 carbon atoms (a C1 to C14 alkyl group, for example,a C1 to C12 alkyl group, for example, an n-octyl group, a 2-ethylhexylgroup, or an n-dodecyl group), an aromatic hydrocarbon group having 6 to28 carbon atoms (a C6 to C28 aryl group, for example a C6 to C14 arylgroup or a C6 to C10 aryl group), or an aromatic heterocyclic grouphaving 3 to 25 ring-member atoms (a C1 to C25 heteroaryl group, forexample a C1 to C20 heteroaryl group or a C1 to C10 heteroaryl group),

a may be an integer of 1 or 4.

In Chemical Formula 5B and Chemical Formula 5C,

Z₁ may be CR_(a)R_(b), NR_(c), O, S, Se, or Te, wherein R_(a), R_(b),and R_(c) may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms (a C1 to C14 alkyl group,for example, a C1 to C12 alkyl group, for example, an n-octyl group, a2-ethylhexyl group, or an n-dodecyl group), an aromatic hydrocarbongroup having 6 to 14 carbon atoms (a C6 to C14 aryl group, for example aC6 to C10 aryl group), or an aromatic heterocyclic group having 3 to 25ring-member atoms (a C1 to C25 heteroaryl group, for example a C1 to C20heteroaryl group or a C1 to C10 heteroaryl group), or R_(a) and R_(b)may be linked to each other to provide a spiro structure (e.g.,fluorenyl group),

R₁, R₂, R₃, and R₄ may each independently be hydrogen, a linear orbranched hydrocarbon group having 1 to 14 carbon atoms (a C1 to C14alkyl group, for example, a C1 to C12 alkyl group, for example, ann-octyl group, a 2-ethylhexyl group, or an n-dodecyl group), an aromatichydrocarbon group having 6 to 28 carbon atoms (a C6 to C28 aryl group,for example a C6 to C14 aryl group or a C6 to C10 aryl group), or anaromatic heterocyclic group having 3 to 25 ring-member atoms (a C1 toC25 heteroaryl group, for example a C1 to C20 heteroaryl group or a C1to C10 heteroaryl group),

a and b may each independently be an integer of 1 to 3, and

c and d may each independently be an integer of 1 to 3.

In Chemical Formula 5D and Chemical Formula 5E,

R₁, R₂, R₃, R₄, and R₅ may each independently be hydrogen, a linear orbranched hydrocarbon group having 1 to 14 carbon atoms (a C1 to C14alkyl group, for example, a C1 to C12 alkyl group, for example, ann-octyl group, a 2-ethylhexyl group, or an n-dodecyl group), an aromatichydrocarbon group having 6 to 28 carbon atoms (a C6 to C28 aryl group,for example a C6 to C14 aryl group or a C6 to C10 aryl group), or anaromatic heterocyclic group having 3 to 25 ring-member atoms (a C1 toC25 heteroaryl group, for example a C1 to C20 heteroaryl group or a C1to C10 heteroaryl group),

a, b, c, d, and e may each independently be an integer of 1 to 4.

For example, Y may be a group represented by Group 5.

In Group 5,

R₁, R₂, and R₄ may each independently be hydrogen, a linear or branchedhydrocarbon group having 1 to 14 carbon atoms (a C1 to C14 alkyl group,for example a C1 to C12 alkyl group), an aromatic hydrocarbon grouphaving 6 to 28 carbon atoms (a C6 to C28 aryl group, for example a C6 toC14 aryl group or a C6 to C10 aryl group), or an aromatic heterocyclicgroup having 3 to 25 ring-member atoms (a C1 to C25 heteroaryl group,for example a C1 to C20 heteroaryl group or a C1 to C10 heteroarylgroup),

R₃ may each independently be hydrogen or a linear or branchedhydrocarbon group having 1 to 14 carbon atoms (a C1 to C14 alkyl groupor a C1 to C12 alkyl group), and

a hydrogen atom of an aromatic ring of a Group 5 structure may beoptionally substituted by a linear or branched hydrocarbon group having1 to 14 carbon atoms.

The linear or branched hydrocarbon group having 1 to 14 carbon atoms maybe, for example, a methyl group, an ethyl group, an n-propyl group, anisopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group,a tert-butyl group, an n-pentyl group, an isopentyl group, a tert-pentylgroup, a neopentyl group, a 1,2-dimethylpropyl group, an n-hexyl group,an isohexyl group, a 1,3-dimethylbutyl group, a 1-isopropyl propylgroup, a 1,2-dimethylbutyl group, an n-heptyl group, a 1,4-dimethylpentyl group, a 3-ethyl pentyl group, a 2-methyl-1-isopropyl propylgroup, a 1-ethyl-3-methyl butyl group, an n-octyl group, a 2-ethylhexylgroup, a 3-methyl-1-isopropyl butyl group, a 2-methyl-1-isopropyl group,a 1-tert-butyl-2-methyl propyl group, an n-nonyl group, a3,5,5-trimethyl hexyl group, an n-decyl group, an isodecyl group, ann-undecyl group, a 1-methyldecyl group, an n-dodecyl group, ann-tridecyl group, an n-tetradecyl group, and the like.

The aromatic hydrocarbon group having 6 to 28 carbon atoms may be aphenyl group, a naphthyl group, a biphenyl group, a fluorenyl group, ananthryl group, a pyrenyl group, an azulenyl group, an acenaphthylenylgroup, a terphenyl group, and a phenanthryl group.

In an embodiment, Y may be desirably a moiety represented by one of(5-1) to (5-7), or more desirably a moiety represented by one of (5-2)and (5-5).

In Group 5, R₁, R₂, R₃, and R₄ may each independently be a linear orbranched (saturated) hydrocarbon group having 1 to 14 carbon atoms or anaromatic hydrocarbon group having 6 to 14 carbon atoms, and desirably ann-octyl group, a 2-ethylhexyl group, or an n-dodecyl group. Such Y mayappropriately control the HOMO level of the copolymer. In addition, ahigher hole injection property, a higher triplet energy level, a lowerdrive voltage, a film-forming property, or the balance of any two ormore of these (particularly a hole injection property and a film-formingproperty) may be achieved.

As described above, the copolymer according to the present embodimentmay be composed of Structural Unit (1) alone. Alternatively, thecopolymer according to the present embodiment may further include otherstructural units in addition to Structural Unit (1). Other structuralunits are not particularly limited as long as they do not impair theeffect of the copolymer (especially high triplet energy level and lowdriving voltage). Specifically, a structural unit as represented inGroup 6 may be mentioned. Hereinafter, the structural unit representedin Group 6 is also referred to as “Structural Unit (2).”

In Group 6,

a hydrogen atom of the aromatic ring of a Group 6 structure may beoptionally substituted by a linear or branched hydrocarbon group having1 to 14 carbon atoms (a C1 to C14 alkyl group or a C1 to C12 alkylgroup), or an aromatic hydrocarbon group having 6 to 28 carbon atoms (aC6 to C28 aryl group, for example a C6 to C20 aryl group).

The composition of Structural Unit (2) in the copolymer of the presentembodiment is not particularly limited. In consideration of the ease offilm-forming by the obtained polymer compound and the new improvementeffect of film strength, Structural Unit (2) may be included in anamount of greater than or equal to about 1 mole percent (mol %) and lessthan or equal to about 10 mol % based on the total structural unitsconstituting the copolymer. On the other hand, when the copolymerincludes two or more Structural Units (2), the content of StructuralUnit (2) means the total amount of Structural Units (2).

The weight average molecular weight (Mw) of the copolymer is notparticularly limited as long as the desired effect of the presentdisclosure is obtained. The weight average molecular weight (Mw) may be,for example, about 8,000 to about 400,000, or for example greater thanabout 15,000 and less than about 350,000. With such a weight averagemolecular weight, it is possible to appropriately adjust the viscosityof the coating composition for forming a layer (for example, a holeinjection layer, a hole transport layer) formed using the copolymer toform a layer having a uniform film thickness.

The number average molecular weight (Mn) of the copolymer is notparticularly limited as long as the desired effect of the presentdisclosure is obtained. The number average molecular weight (Mn) may be,for example, about 5,000 to about 190,000, or for example about 9,000.With such a number average molecular weight, it is possible toappropriately adjust the viscosity of the coating composition forforming a layer (for example, a hole injection layer, a hole transportlayer) formed using the copolymer and to form a layer having a uniformfilm thickness. In addition, a polydispersity (weight average molecularweight/number average molecular weight) of the copolymer of the presentembodiment may be, for example, about 1.4 to about 4.0, or for examplegreater than about 1.5 and less than about 3.6.

Herein, the measurement of the number average molecular weight (Mn) andthe weight average molecular weight (Mw) is not particularly limited andmay be applied by using a known method or by appropriately changing theknown methods. In the present specification, the number averagemolecular weight (Mn) and the weight average molecular weight (Mw) usevalues measured by the following method. The polydispersity (Mw/Mn) ofthe polymer is calculated by dividing the weight average molecularweight (Mw) by the number average molecular weight (Mn) measured by thefollowing method.

Measurement of Number Average Molecular Weight (Mn) and Weight AverageMolecular Weight (Mw)

The number average molecular weight (Mn) and the weight averagemolecular weight (Mw) of the copolymer are measured under the followingconditions by SEC (Size Exclusion Chromatography) using polystyrene as astandard material.

(SEC Measurement Condition)

Analysis equipment (SEC): Shimadzu Corporation, Prominence

Column: Polymer Laboratories, PLgel MIXED-B

Column temperature: 40° C.

Flow rate: 1.0 mL/min

Injection amount of sample solution: 20 μL (concentration: about 0.05 wt%)

Eluent: tetrahydrofuran (THF)

Detector (UV-VIS detector): Shimadzu Corporation, SPD-10AV

Standard sample: polystyrene.

The terminal end of the main chain of the copolymer of the presentembodiment is not particularly limited and is appropriately defineddepending on the type of raw material used, but is usually a hydrogenatom.

The copolymer of the present embodiment may be synthesized by using aknown organic synthesis method. The specific synthesis method of thecopolymer may be easily understood by a person of an ordinary skill inthe art referring to the examples to be described later. Specifically,the copolymer of the present embodiment may be prepared by apolymerization reaction using at least one monomer (1) represented byChemical Formula 1′, or a copolymerization reaction using one or moretypes of monomers (1) represented by Chemical Formula 1′, and anothermonomer corresponding to the other structural unit (e.g., StructuralUnit (2)).

Alternatively, it may be prepared by a copolymerization reaction usingone or more monomers (1-1) represented by Chemical Formula 1-1′ and oneor more monomers (1-2) represented by Chemical Formula 1-2′ or acopolymerization reaction using one or more monomers (1-1) representedby Chemical Formula 1-1′, one or more types of monomer (1-2) representedby Chemical Formula 1-2′, and another monomer corresponding to the otherstructural unit (e.g., Structural Unit (2)).

The monomers used for the polymerization of the copolymer according tothe present disclosure may be synthesized by appropriately combining aknown synthesis reaction, and their structures may be confirmed by knownmethods (for example, NMR, LC-MS, etc.).

In Chemical Formula 1′, Chemical Formula 1-1′, and Chemical Formula1-2′, L₁, Ar₁, Ar₂, and Y are the same as in Chemical Formula 1. Z₁, Z₂,Z₁′, Z₂′, Z₁″, and Z₂″ may each independently a halogen atom (a fluorineatom, a chlorine atom, a bromine atom, an iodine atom, particularly abromine atom) or a functional group represented by Chemical Formula D.On the other hand, in Chemical Formula D, R_(A) to R_(D) may eachindependently be an alkyl group having 1 to 3 carbon atoms. In anembodiment, R_(A) to R_(D) may be a methyl group.

Z₁ and Z₂ of Chemical Formula 1′ may be the same or different. Likewise,Z₁′ and Z₂′ in Chemical Formula 1-1′ may be the same or different fromeach other. Z₁″ and Z₂″ of Chemical Formula 1-2′ may be the same ordifferent from each other. In an embodiment, Z₁ and Z₂ of above ChemicalFormula 1′ may be different. In an embodiment, Z₁′ and Z₂′ in ChemicalFormula 1-1′ may be the same; Z₁″ and Z₂″ in Chemical Formula 1-2′ maybe the same; and Z₁′ and Z₂′ of Chemical Formula 1-1′ are different fromZ₁″ and Z₂″ of Chemical Formula 1-2′.

Electroluminescence Device Material

As described above, the copolymer according to the present embodimentmay be used as an electroluminescence device material. In other words,an electroluminescence device includes a pair of electrodes and one ormore organic layers between the electrodes and including the copolymeror the electroluminescence device material of the present embodiment.Due to the copolymer, an electroluminescence device material having ahigh triplet energy level (current efficiency) and a low driving voltageis also provided.

In addition, the copolymer according to the present embodiment exhibitshigh solubility in a solvent and high heat resistance. Therefore, thecopolymer may be easily made into a film (thin film) by the wet(coating) method. Accordingly, in another embodiment, anelectroluminescence device material including the aforementionedcopolymer is provided.

In addition, the use of the copolymer as electroluminescence devicematerial is provided.

Electroluminescence Device

As described above, the copolymer according to the present embodimentmay be used for an electroluminescence device. In other words, anelectroluminescence device includes a pair of electrodes and one or moreorganic layers between the electrodes and including the copolymer or theelectroluminescence device material of the present embodiment. Such anelectroluminescence device may exhibit improved luminous efficiency(especially excellent luminous efficiency with a low driving voltage).Moreover, such an electroluminescence device may exhibit high luminousefficiency (especially excellent luminous efficiency with a low drivevoltage).

Accordingly, according to an embodiment, an electroluminescence deviceincludes a first electrode and a second electrode, and one or moreorganic layers between the first electrode and the second electrode,wherein at least one layer of the organic layer includes theaforementioned copolymer. The purpose (or effect) of the presentdisclosure may also be achieved by the electroluminescence deviceaccording to the present embodiment. In an embodiment, theelectroluminescence device further includes a light emitting layerbetween the electrodes and including a light emitting material capableof emitting light from triplet excitons. On the other hand, theelectroluminescence device of the present embodiment may be an exampleof the electroluminescence device according to the present disclosure.

In addition, the present embodiment provides a method of manufacturingan electroluminescence device that includes a pair of electrodes and atleast one organic layer disposed between the electrodes and includingthe copolymer according to the present embodiment. At least one of thelayers is formed by a coating method. In addition, by this method, thepresent embodiment provides an electroluminescence device in which atleast one layer of the organic layer is formed by a coating method.

The aforementioned copolymer, and electroluminescence device material(EL device material) according to the present embodiment (hereinaftercollectively, also referred to as “copolymer/EL device material”) haveimproved solubility in an organic solvent. For this reason, thecopolymer/EL device material according to the present embodiment may beused for manufacturing devices (especially thin films) by a coatingmethod (wet process). For this reason, the present embodiment provides aliquid composition including the copolymer and a solvent or a dispersivemedium. Such a liquid composition is an example of the liquidcomposition according to the present disclosure.

In addition, as described above, the electroluminescence device materialaccording to the embodiment may be used for the manufacture of devices(particularly thin films) by a coating method (wet process). In view ofthe above, the present embodiment provides a thin film including theaforementioned copolymer. Such a thin film is an example of the thinfilm according to the present disclosure.

Further, the copolymer/EL device material according to the presentembodiment has improved hole injection properties and hole mobility. Forthis reason, it may be also desirably used in the formation of any oneorganic layer of a hole injection material, a hole transport material,or a light emitting material (host). Among them, from the viewpoint ofhole transportability, it may be used as a hole injection material or ahole transport material, and particularly a hole transport material.

Hereinafter, referring to FIG. 1, an electroluminescence deviceaccording to the present embodiment is described in detail. FIG. 1 is aschematic representation showing an electroluminescence device accordingto the present embodiment. In addition, in this specification, an“electroluminescence device” may be abbreviated as “EL device.”

As shown in FIG. 1, the EL device 100 according to the presentembodiment includes a substrate 110, a first electrode 120 on thesubstrate 110, a hole injection layer 130 on the first electrode 120, ahole transport layer 140 on the hole injection layer 130, a lightemitting layer 150 on hole transport layer 140, an electron transportlayer 160 on the light emitting layer 150, an electron injection layer170 on the electron transport layer 160, and a second electrode 180 onthe electron injection layer 170.

Herein, the copolymer/EL device material according to the presentembodiment is included in, for example, any one organic layer (organicfilm) disposed between the first electrode 120 and the second electrode180. Specifically, the copolymer/EL device material may be included inthe hole injection layer 130 as a hole injection material, in the holetransport layer 140 as a hole transport material, or in the lightemitting layer 150 as a light emitting material (host). The copolymer/ELdevice material may be included in the hole injection layer 130 as ahole injection material or in the hole transport layer 140 as a holetransport material. The copolymer/EL device material may be included inthe hole transport layer 140 as a hole transport material. That is, inan embodiment, the organic layer including the copolymer/EL devicematerial may be a hole transport layer, a hole injection layer, or alight emitting layer. In an embodiment, the organic layer including thecopolymer/EL device material may be a hole transport layer or a holeinjection layer. In an embodiment, the organic layer including thecopolymer/EL device material may be a hole transport layer.

In addition, the organic layer including the copolymer according to thepresent embodiment/EL device material may be formed by a coating method(solution coating method). Specifically, the organic layer may be formedby a solution coating method such as a spin coating method, a castingmethod, a micro gravure coating method, a gravure coating method, a barcoating method, a roll coating method, a wire bar coating method, a dipcoating method, a spray coating method, a screen-printing method, aflexographic printing method, an offset printing method, an inkjetprinting method, and the like.

As the solvent used in the solution coating method, any solvent may beused as long as it is capable of dissolving the copolymer/EL devicematerial, and the solvent may be appropriately selected according totypes of the copolymer. For example, the solvent may be toluene, xylene,ethylbenzene, diethylbenzene, mesitylene, propylbenzene,cyclohexylbenzene, dimethoxybenzene, anisole, ethoxytoluene,phenoxytoluene, isopropylbiphenyl, dimethylanisole, phenyl acetate,phenyl propionate, methyl benzoate, ethyl benzoate, cyclohexane, and thelike. An amount of the solvent used is not particularly limited, butconsidering the ease of coating, a concentration of the copolymer maydesirably be greater than or equal to about 0.1 wt % and less than orequal to about 10 wt %, or greater than or equal to about 0.5 wt % andless than or equal to about 5 wt %.

In addition, the film-formation method of layers other than the organiclayer including the copolymer/EL device material/is not specificallylimited. The layers other than the organic layer including thecopolymer/EL device material according to the present embodiment may beformed by, for example, a vacuum deposition method or may be formed by asolution coating method.

The substrate 110 may be a substrate used in a general EL device. Forexample, the substrate 110 may be a semiconductor substrate such as aglass substrate, a silicon substrate, and the like, or a transparentplastic substrate.

On the substrate 110, the first electrode 120 is formed. The firstelectrode 120 is specifically an anode, and is formed by a materialhaving a large work function among a metal, an alloy, or a conductivecompound. For example, the first electrode 120 may be formed as atransmissive electrode by indium tin oxide (In₂O₃—SnO₂: ITO), indiumzinc oxide (In₂O₃—ZnO), tin oxide (SnO₂), zinc oxide (ZnO) or the likedue to improved transparency and conductivity. The first electrode 120may be formed as a reflective electrode by laminating magnesium (Mg),aluminum (Al), or the like on the transparent conductive layer. Afterforming the first electrode 120 on the substrate 110, washing andUV-ozone treatment may be performed as necessary.

On the first electrode 120, the hole injection layer 130 is formed. Thehole injection layer 130 is a layer that facilitates injection of holesfrom the first electrode 120, and may be formed to have a thickness (dryfilm thickness; the same below) of specifically greater than or equal toabout 10 nm and less than or equal to about 1000 nm, or greater than orequal to about 20 nm and less than or equal to about 50 nm.

The hole injection layer 130 may be formed of a known hole injectionmaterial. The known hole injection material of the hole injection layer130 may include, for example, triphenylamine-containing poly(etherketone) (TPAPEK), 4-isopropyl-4′-methyldiphenyl iodoniumtetrakis(pentafluorophenyl) borate (PPBI),N,N′-diphenyl-N,N′-bis-[4-(phenyl-m-tolyl-amino)-phenyl]-biphenyl-4,4′-diamine(DNTPD), copper phthalocyanine,4,4′,4″-tris(3-methylphenylphenylamino)triphenylamine (m-MTDATA),N,N′-di(1-naphthyl)-N,N′-diphenylbenzidine (NPB),4,4′,4″-tris(diphenylamino)triphenylamine (TDATA),4,4′,4″-tris(N,N-2-naphthylphenylamino)triphenylamine (2-TNATA),polyaniline/dodecylbenzenesulphonic acid,poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS),and polyaniline/10-camphorsulfonic acid, and the like.

On the hole injection layer 130, the hole transport layer 140 is formed.The hole transport layer 140 is a layer having a function oftransporting holes, and may be formed with a thickness of, for example,greater than or equal to about 10 nm and less than or equal to about 150nm, and more specifically greater than or equal to about 20 nm and lessthan or equal to about 50 nm. The hole transport layer 140 may be formedby a solution coating method using the copolymer according to thepresent embodiment. According to this method, the durability(luminescence life-span) of EL device 100 may be extended. In addition,the performance (luminous efficiency) of the EL device 100 may beimproved. In addition, since the hole transport layer may be formed bythe solution coating method, a large area may be formed efficiently.

However, when one organic layer of the EL device 100 includes thecopolymer according to the present embodiment, the hole transport layer140 may be formed of a known hole transport material. The known holetransport material may include, for example, 1,1-bis[(di-4-tolylamino)phenyl] cyclohexane (TAPC), a carbazole derivative such asN-phenylcarbazole, polyvinylcarbazole, and the like,N,N′-bis(3-methylphenyl)-N,N′-diphenyl-[1,1-biphenyl]-4,4′-diamine(TPD), 4,4′,4″-tris(N-carbazolyl) triphenylamine (TCTA), andN,N′-di(1-naphthyl)-N,N′-diphenylbenzidine (NPB).

On the hole transport layer 140, the light emitting layer 150 is formed.The light emitting layer 150 is a layer that emits light byfluorescence, phosphorescence, and the like, and is formed using avacuum deposition method, a spin coating method, an inkjet printingmethod, or the like. The light emitting layer 150 may be formed with athickness of, for example, about 10 nm to about 60 nm, and morespecifically about 20 nm to about 50 nm. As the light emitting materialof the light emitting layer 150 may include a known light emittingmaterial. However, the light emitting material included in the lightemitting layer 150 is desirably a light emitting material capable ofemitting light (i.e., phosphorescence emission) from triplet excitons.In such a case, the driving life-span of the EL device 100 may befurther improved.

The light emitting layer 150 is not particularly limited and may have aknown configuration. Desirably, the light emitting layer may include asemiconductor nanoparticle or an organometallic complex. That is, in anembodiment of the present disclosure, the organic layer has a lightemitting layer including semiconductor nanoparticles or organometalliccomplexes. When the light emitting layer includes semiconductornanoparticles, the EL device may be a quantum dot electroluminescencedevice (QLED) or a quantum dot light emitting diode. In addition, whenthe light emitting layer includes an organometallic complex, the ELdevice is an organic electroluminescence device (OLED).

In the form in which the light emitting layer includes semiconductornanoparticles (QLED), the light emitting layer may include a pluralityof semiconductor nanoparticles (quantum dots) arranged in a single layeror a plurality of layers. Herein, the semiconductor nanoparticles(quantum dots) may be particles of predetermined sizes that have aquantum confinement effect. The diameter of the semiconductornanoparticles (quantum dots) is not particularly limited but is greaterthan or equal to about 1 nm and less than or equal to about 10 nm.

The semiconductor nanoparticles (quantum dots) arranged in the lightemitting layer may be synthesized by a wet chemical process, anorganometal chemical deposition process, a molecular beam epitaxyprocess, or another similar process. Among them, the wet chemicalprocess is a method of growing a particle by putting a precursormaterial in an organic solvent.

In the wet chemistry process, when crystals grow, the organic solventnaturally coordinates to the surface of the quantum dot crystals andacts as a dispersing agent, thereby controlling the growth of thecrystals. For this reason, in the wet chemical process, compared withgas phase deposition methods, such as metal organic chemical vapordeposition (MOCVD) and molecular beam epitaxy (MBE), growth ofsemiconductor nanoparticles may be easily controlled at a low cost.

The semiconductor nanoparticles (quantum dots) may adjust energybandgaps by adjusting their sizes, so that light of various wavelengthsmay be obtained from the light emitting layer (quantum dot lightemitting layer). Thus, a plurality of differently sized quantum dots mayembody a display that discharges (or emits) light of multiplewavelengths. The sizes of the quantum dots may be selected to emit red,green, and blue light to form a color display. In addition, the sizes ofthe quantum dots may be combined so that various color lights emit whitelight.

The semiconductor nanoparticles (quantum dots) may be semiconductormaterial such as a Group II-VI semiconductor compound; a Group III-Vsemiconductor compound; a Group IV-VI semiconductor compound; a Group IVelement or compound; or a combination thereof.

The Group II-VI semiconductor compound is not particularly limited, butincludes, for example, a binary compound such as CdSe, CdTe, ZnS, ZnSe,ZnTe, ZnO, HgS, HgSe, HgTe, or a mixture thereof; a ternary compoundsuch as CdSeS, CdSeTe, CdSTe, ZnSeS, ZnTeSe, ZnSTe, HgSeS, HgSeTe,HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe,HgZnTe, or a quaternary compound such as CdZnSeS, CdZnSeTe, CdZnSTe,CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe, or a mixturethereof.

The Group III-V semiconductor compound is not particularly limited, butincludes, for example, a binary compound such as GaN, GaP, GaAs, GaSb,AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, or a mixture thereof; aternary compound such as GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs,AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, or amixture thereof; or a quaternary compound such as GaAlNAs, GaAlNSb,GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP,InAlNAs, InAlNSb, InAlPAs, InAlPSb, or a mixture thereof.

The Group IV-VI semiconductor compound is not particularly limited, butincludes, for example, a binary compound such as SnS, SnSe, SnTe, PbS,PbSe, PbTe, or a mixture thereof; a ternary compound such as SnSeS,SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, or a mixturethereof; or a quaternary compound such as SnPbSSe, SnPbSeTe, SnPbSTe, ora mixture thereof.

The Group IV element or compound is not particularly limited, butincludes, for example, a single element compound such as Si, Ge, or amixture thereof; and a binary compound such as SiC, SiGe, or a mixturethereof.

The semiconductor nanoparticles (quantum dots) may have a homogeneoussingle structure or a double structure of a core-shell. The core-shellmay include different materials. The material constituting each core andshell may be made of different semiconductor compounds. However, anenergy bandgap of the shell material is larger than an energy bandgap ofthe core material. Specifically, structures such as ZnTeSe/ZnSe/ZnS,CdSe/ZnS, InP/ZnS, and the like are desirable.

For example, a process of producing a quantum dot having a core(CdSe)-shell (ZnS) structure is described. First, crystals are formed byinjecting core (CdSe) precursor materials of (CH₃)₂Cd (dimethylcadmium), TOPSe (trioctylphosphine selenide) and the like into anorganic solvent using TOPO (trioctylphosphine oxide) as a surfactant. Atthis time, after maintaining a certain time at high temperature so thatthe crystals grow to a certain size, the precursor materials of theshell (ZnS) are injected, to form a shell on the surface of the corealready generated. As a result, a quantum dot of CdSe/ZnS capped withTOPO may be produced.

In addition, in the embodiment (OLED) in which the light emitting layerincludes an organometallic complex, the light emitting layer 150 mayinclude, for example 6,9-diphenyl-9′-(5′-phenyl-[1,1′:3′,1″-terphenyl]-3-yl)3,3′-bi[9H-carbazole],3,9-diphenyl-5-(3-(4-phenyl-6-(5′-phenyl-[1,1′:3′,1″-terphenyl]-3-yl)-1,3,5,-triazin-2-yl)phenyl)-9H-carbazole,9,9′-diphenyl-3,3′-bi[9H-carbazole], tris(8-quinolinato)aluminum (Alq₃),4,4′-bis(carbazol-9-yl)biphenyl (CBP), poly(n-vinyl carbazole (PVK),9,10-di(naphthalene)anthracene (ADN),4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA),1,3,5-tris(N-phenyl-benzimidazol-2-yl)benzene (TPBI),3-tert-butyl-9,10-di(naphth-2-yl)anthracene (TBADN), distyrylarylene(DSA), 4,4′-bis(9-carbazole)-2,2′-dimethyl-bipheny (dmCBP), and thelike, as a host material.

In addition, the light emitting layer 150 may include, for example,perylene and a derivative thereof, rubrene and a derivative thereof,coumarin and a derivative thereof,4-dicyanomethylene-2-(pdimethylaminostyryl)-6-methyl-4H-pyran (DCM) anda derivative thereof, an iridium (Ir) complex such asbis[2-(4,6-difluorophenyl)pyridinate]picolinate iridium(III) (Flrpic)),bis(1-phenylisoquinoline) (acetylacetonate)iridium(III)(Ir(piq)₂(acac)), tris(2-phenylpyridine)iridium (III) (Ir(ppy)₃),tris(2-(3-p-xylyl)phenyl)pyridine iridium (III), an osmium (Os) complex,a platinum complex, and the like, as a dopant material. Among these, itis desirable that the light emitting material is a light emittingorganometallic complex compound.

A method for forming the light emitting layer is not particularlylimited. It may be formed by coating (solution coating method) coatingcomposition including a semiconductor nanoparticle or an organometalliccomplex. At this time, it is desirable to select a solvent which doesnot dissolve the materials (hole transport material, particularly thecopolymer or polymeric composition) in the hole transport layer as thesolvent constituting the coating composition.

On the light emitting layer 150, an electron transport layer 160 isformed. The electron transport layer 160 is a layer having a function oftransporting electrons, and is formed using a vacuum deposition method,a spin coating method, an inkjet method, or the like. For example, theelectron transport layer 160 may be formed to have a thickness ofgreater than or equal to about 15 nm and less than or equal to about 50nm.

The electron transport layer 160 may be formed of a known electrontransport material. The known electron transport material may include,for example, (8-quinolinato) lithium (lithium quinolate, Liq),tris(8-quinolinato) aluminum (Alq3) and a compound having anitrogen-containing aromatic ring. Examples of the compound having thenitrogen-containing aromatic ring may include, for example, a compoundincluding a pyridine ring such as1,3,5-tri[(3-pyridyl)-phen-3-yl]benzene), a compound including atriazine ring such as2,4,6-tris(3′-(pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine), a compoundincluding an imidazole ring such as2-(4-(N-phenylbenzoimidazolyl-1-yl-phenyl)-9,10-dinaphthylanthracene or1,3,5-tris(N-phenyl-benzimidazol-2-yl)benzene (TPBI). The electrontransport material may be used alone or as a mixture of two or morethereof.

On the electron transport layer 160, an electron injection layer 170 isformed. The electron injection layer 170 is a layer having a function offacilitating injection of electrons from the second electrode 180. Theelectron injection layer 170 is formed using a vacuum deposition methodor the like. The electron injection layer 170 may be formed to have athickness of greater than or equal to about 0.1 nm and less than orequal to about 5 nm, and more specifically, greater than or equal toabout 0.3 nm and less than or equal to about 2 nm. As a material forforming the electron injection layer 170, any known material may beused. For example, the electron injection layer 170 may be formed of alithium compound such as (8-quinolinato) lithium (lithium quinolate,Liq) and lithium fluoride (LiF), sodium chloride (NaCl), cesium fluoride(CsF), lithium oxide (Li₂O), or barium oxide (BaO).

On the electron injection layer 170, a second electrode 180 is formed.The second electrode 180 is formed using a vacuum deposition method orthe like. Specifically, the second electrode 180 is a cathode, and isformed by a material having a small work function such as metals,alloys, or conductive compounds. For example, the second electrode 180is may be formed as a reflective electrode with a metal such as lithium(Li), magnesium (Mg), aluminum (Al), calcium (Ca), or aluminum-lithium(Al—Li), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), or thelike. The second electrode 180 may be formed to have a thickness ofgreater than or equal to about 10 nm and less than or equal to about 200nm, and more and specifically, greater than or equal to about 50 nm andless than or equal to about 150 nm. Alternatively, the second electrode180 may be formed as a transmissive electrode by a thin film of lessthan or equal to about 20 nm of a metal material or a transparentconductive layer such as indium tin oxide (In₂O₃—SnO₂), and indium zincoxide (In₂O₃—ZnO).

The EL device 100 has been described above as an example of theelectroluminescence device. The EL device 100 according to the presentembodiment further improves durability (luminescence life-span) byincluding an organic layer (particularly a hole transport layer or ahole injection layer) including the copolymer. In addition, the luminousefficiency (current efficiency) may be further improved and the drivingvoltage may be reduced.

The stacked structure of the EL device 100 according to the presentembodiment is not limited to the above embodiments. The EL device 100according to the present embodiment may have another known stackedstructure. For example, in the EL device 100, one or more layers of thehole injection layer 130, the hole transport layer 140, the electrontransport layer 160 and the electron injection layer 170 may be omittedor another layer may be further included. In addition, each layer of theEL device 100 may be formed in a single layer or in a plurality oflayers.

For example, the EL device 100 may further include a hole blocking layerbetween the hole transport layer 140 and the light emitting layer 150 inorder to prevent excitons or holes from diffusing into the electrontransport layer 160. The hole blocking layer may be formed by, forexample, an oxadiazole derivative, a triazole derivative, or aphenanthroline derivative.

In addition, the copolymer according to the present embodiment may beapplied to electroluminescence devices other than the QLED or OLED.Other electroluminescence devices including the copolymer according tothe present embodiment may include, but are not particularly limited to,for example, organic inorganic perovskite light emitting devices.

EXAMPLES

The embodiments are described in more detail using the followingexamples and comparative examples. However, the technical range of thepresent disclosure is not limited to the following examples. In thefollowing examples, unless specifically described, each operation isperformed at room temperature (25° C.). In addition, unless specificallystated, “%” and “a part” mean “wt %” and “a part by weight,”respectively.

Synthesis of Monomer M-1

Monomer M-1 is synthesized according to Reaction Scheme M-1.

2-bromo-9,9′-spirobi[9H-fluorene] (15.6 g), 2-amino-9,9-dimethylfluorene (30.0 g), a 1,1′-bis(diphenylphosphino)ferrocene] palladium(II) dichloride dichloromethane adduct (3.09 g), sodium t-butoxide (14.6g), and toluene (190 mL) are added to a 500 mL four-necked flask, andstirred under a nitrogen atmosphere at 100° C. for 4 hours. Theresulting reaction mixture is allowed to cool to room temperature (about25° C.), and an insoluble matter is filtered off by using Celite®). Thesolvent is removed under a reduced pressure, and the residue is purifiedby column chromatography, obtainingN-(9,9′-dimethyl-9H-fluoren-2-yl)-9,9′-spirobi[fluorene]-2-amine (33.4g, Yield: 84.0%).

3,6-dichloro carbazole (100.0 g), 4-bromo-4′-iodine biphenyl (167 g),copper iodide (4.03 g), sodium t-butoxide (81.4 g),trans-1,2-cyclohexanediamine (9.67 g), and 1,4-dioxane (1060 mL) areadded to a 2 L four-necked flask, and heated and stirred under anitrogen atmosphere at 100° C. for 4 hours.

The reaction mixture is allowed to cool to room temperature, and aninsoluble matter is filtered off by using Celite®. The solvent isremoved under a reduced pressure, and the residue is dissolved intoluene (800 mL). The obtained solution is washed with 1 L of water,2N—HCl (500 mL×2), and water (500 mL×2), and dried with MgSO₄. Thewashed solution is filtered with Celite® silica gel. The toluene isremoved under a reduced pressure, and the residue is recrystallized witha mixed solvent of toluene/ethanol and dried, thereby obtaining9-(4′bromo-[1,1′-biphenyl]-4-yl) 3,6-dichloro-9H-carbazole (81.5 g,Yield: 74.8%).

N-(9,9′-dimethyl-9H-fluoren-2-yl)-9,9′-spirobi[fluorene]-2-amine (8.00g), 9-(4′bromo-[1,1′-biphenyl]-4-yl) 3,6-dichloro-9H-carbazole (7.13 g),palladium acetate (Pd(OAc)₂) (0.171 g), tri-tert-butylphosphoniumtetrafluoroborate (t-Bu₃P.BF₄, 0.332 g), sodium t-butoxide (2.93 g), andtoluene (150 mL) are added to a 500 mL four-necked flask, and stirredunder a nitrogen atmosphere at 100° C. for 3 hours.

The resulting insoluble matter is filtered off with Celite®, and thenactivated carbon (3 g). Zeolite (3 g) is added to the filtrate, andstirred at 110° C. for 30 minutes. The resulting solids are filtered offwith Celite®, and the filtrate is passed through silica gel.

The solvent is removed under a reduced pressure, and the residue ispurified by column chromatography (silica gel, hexane/toluene),recrystallized with a mixed solvent of toluene and acetonitrile, anddried, thereby obtainingN-(4′-(3,6-dichloro-9H-carbazol-9-yl)-[1,1′-biphenyl]-4-yl)-N-(9,9′-dimethyl-9H-fluoren-2-yl)-9,9′-spirobi[fluorene]-2-amine(6.57 g, Yield: 76.0%).

N-(4′-(3,6-dichloro-9H-carbazol-9-yl)-[1,1′-biphenyl]-4-yl)-N-(9,9′-dimethyl-9H-fluoren-2-yl)-9,9′-spirobi[fluorene]-2-amine(6.56 g), bis(pinacolato)diboron (bis(pinacolato)diboron) (6.79 g),potassium acetate (6.25 g), tris(dibenzylideneacetone) dipalladium(Pd₂(dba)₃) (0.48 g),2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl (XPhos) (0.754 g),and 1,4-dioxane (160 mL) are added to a 200 mL four-necked flask, andrefluxed under a nitrogen atmosphere for 4 hours. The reaction solutionis allowed to cool to room temperature, and the resulting solid isfiltered off with Celite®. The solvent is removed under a reducedpressure, the residue is dissolved in toluene (100 mL), and activatedcarbon (2 g) and zeolite (2 g) are added, and then stirred at 130° C.for 30 minutes. The solids are filtered off with Celite®, and thefiltrate is passed through silica gel. The solvent is removed under areduced pressure, the residue is recrystallized with a mixed solvent oftoluene and hexane, and dried, thereby obtaining Monomer M-1 (6.84 g,Yield: 59.3%).

Synthesis of Copolymer P-1

Under a nitrogen atmosphere, Monomer M-1 (1.15 g),2,7-dibromo-9,9-dioctyl fluorene (0.581 g), palladium acetate (2.40 mg),tris(2-methoxy phenyl)phosphine (19.3 mg), toluene (35 mL), and a 20 wt% tetraethylammonium hydroxide aqueous solution (5.46 g) are added to afour-necked flask and stirred at 85° C. for 6 hours. Then, phenylboronic acid (128 mg), bis(triphenylphosphine) palladium (II) dichloride(44.6 mg), and a 20 wt % tetraethylammonium hydroxide aqueous solution(5.46 g) are added to the reaction mixture and stirred at 85° C. for 6hours. Subsequently, sodium N,N-diethyldithiocarbamate trihydrate (3.58g) dissolved in ion exchanged water (35 mL) is added to the mixture,and, stirred at 85° C. for 2 hours.

After separating an organic layer from an aqueous layer, the organiclayer is washed with water, a 3 wt % acetic acid aqueous solution, andagain water. The organic layer is subject to column chromatographycharged with silica gel/alumina. The solvent from the collectedfractions is removed under a reduced pressure. The resulting liquid isadded dropwise to methanol to form a precipitate. The collectedprecipitate is dissolved in toluene, and again added dropwise tomethanol to precipitate a solid. This precipitated solid is filtered anddried, obtaining Copolymer P-1 (0.89 g). The obtained copolymer ismeasured with respect to a weight average molecular weight andpolydispersity by SEC, Mw=15,700, and Mw/Mn=1.60.

Copolymer P-1 is assumed to have Structural Unit P-1 from an input ratioof the monomers.

Production of Quantum Dot Electroluminescence Device D-1

As for a first electrode (an anode), a glass substrate adhered withindium tin oxide (ITO) and a film thickness of 150 nanometers (nm) isused. The ITO-adhered glass substrate is sequentially washed with aneutral detergent, deionized water, and isopropyl alcohol and then,treated with UV-ozone. Subsequently, on this ITO-adhered glasssubstrate, poly(3,4-ethylenedioxyth iophene)/poly(4-styrenesulfonate)(PEDOT/PSS) (Sigma-Aldrich Co., Ltd.) is spin-coated and dried to have adry film thickness of 30 nm. As a result, a hole injection layer havinga thickness (dry film thickness) of 30 nm is formed on the ITO-adheredglass substrate.

On the hole injection layer, a 1.0 weight percent (wt %) toluenesolution of Copolymer P-1 (hole transport material) is applied by spincoating and then heat treated at 230° C. for 60 minutes to form atransport layer with a dry film thickness of 30 nm. As a result, a holetransport layer having a thickness (dry film thickness) of 30 nm isformed on the hole injection layer.

Subsequently, quantum dot dispersion is prepared by dispersing bluequantum dots of ZnTeSe/ZnSe/ZnS (core/shell/shell; an averagediameter=about 10 nm) having a structure shown in FIG. 2 in cyclohexaneat 1.0 wt %. This quantum dot dispersion is spin-coated to have a dryfilm thickness of 30 nm on the hole transport layer (HTL) and dried. Asa result, a quantum dot light emitting layer with a thickness (dry filmthickness) of 30 nm is formed on the hole transport layer (HTL).

When the quantum dot dispersion is irradiated by ultraviolet (UV), lightemitting therefrom has a central wavelength of 462 nm and a full widthat half maximum of 30 nm. On this quantum dot light emitting layer,lithium quinolate (Liq) and 1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene(TPBI) (Sigma-Aldrich Co., Ltd.) as an electron transport material areco-deposited by using a vacuum deposition apparatus. As a result, a 36nm-thick electron transport layer is formed on the quantum dot lightemitting layer.

Using a vacuum deposition apparatus, (8-quinolato) lithium (lithiumquinolate, Liq) is deposited on the electron transport layer. As aresult, a 0.5 nm-thick electron injection layer is formed on theelectron transport layer. Using a vacuum deposition apparatus, aluminum(Al) is deposited on the electron injection layer. As a result, a 100nm-thick second electrode (cathode) is formed on the electron injectionlayer.

Accordingly, a quantum dot electroluminescence device D-1 is obtained.

Example 2 Synthesis of Monomer M-2

Monomer M-2 is synthesized according to Reaction Scheme M-2.

2-(4-biphenyl)amino-9,9-dimethyl fluorene (10.0 g),9-(4′bromo-[1,1′-biphenyl]-4-yl) 3,6-dichloro-9H-carbazole (12.9 g),palladium acetate (Pd(OAc)₂) (0.311 g), tri-tert-butylphosphoniumtetrafluoroborate (t-Bu₃P.BF₄) (0.602 g), sodium t-butoxide (5.31 g),and toluene (280 mL) are added to a 500 mL four-necked flask, andstirred under a nitrogen atmosphere at 100° C. for 5 hours.

An insoluble matter is filtered off with Celite®, and then activatedcarbon (3 g) and zeolite (3 g) are added to the filtrate, and stirred at110° C. for 30 minutes. A resulting solid is filtered off with Celite®,and then passed through silica gel. The solvent is removed under areduced pressure, and the residue is purified by column chromatography(silica gel, hexane/toluene), obtainingN-([1,1′-biphenyl]-4-yl)-N-(4′-(3,6-dichloro-9H-carbazol-9-yl)-[1,1′-biphenyl]-4-yl)-9,9′-dimethyl-9H-fluorene-2-amine(18.5 g, Yield: 89.4%).

TheN-([1,1′-biphenyl]-4-yl)-N-(4′-(3,6-dichloro-9H-carbazol-9-yl)-[1,1′-biphenyl]-4-yl)-9,9′-dimethyl-9H-fluorene-2-amine(10.0 g), bis(pinacolato)diboron (8.52 g), potassium acetate (7.92 g),tris(dibenzylideneacetone) dipalladium (Pd₂(dba)₃) (0.695 g),2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl (XPhos) (0.950 g),and 1,4-dioxane (110 mL) are added to a 200 mL four-necked flask andrefluxed under a nitrogen atmosphere for 4 hours.

The reaction solution is allowed to cool to room temperature, and aformed solid is filtered off with Celite®. The solvent is removed undera reduced pressure, the residue is dissolved in toluene (100 mL), andthen activated carbon (3 g) and zeolite (3 g) are added. The mixture isstirred at 130° C. for 30 minutes.

A solid is filtered off with Celite®, and the filtrate is passed throughsilica gel. The toluene is removed under a reduced pressure, and theresidue is recrystallized with a mixed solvent of toluene and hexane anddried, thereby obtaining Monomer M-2 (6.09 g, Yield: 48.9%).

Synthesis of Copolymer P-2

Under a nitrogen atmosphere, Monomer M-2 (1.57 g),2,7-dibromo-9,9-dioctyl fluorene (0.927 g), palladium acetate (3.8 mg),tris(2-methoxy phenyl)phosphine (30.9 mg), toluene (54 mL), and a 20 wt% tetraethylammonium hydroxide aqueous solution (8.71 g) are added to afour-necked flask, and stirred at 85° C. for 6 hours. Then, phenylboronic acid (204 mg), bis(triphenylphosphine) palladium (II) dichloride(71.1 mg), and a 20 wt % tetraethylammonium hydroxide aqueous solution(8.71 g) are added to the reaction flask, and the reaction mixturestirred at 85° C. for 6 hours. Subsequently, sodiumN,N-diethyldithiocarbamate trihydrate (5.71 g) dissolved in ionexchanged water (54 mL) is added, and the mixture is stirred at 85° C.for 2 hours.

After separating an organic layer from the mixture, the organic layer iswashed with water, a 3 wt % acetic acid aqueous solution, and againwater. The washed organic layer is subject to column chromatographycharged with silica gel/alumina, and the solvent from the collectedfractions is removed under a reduced pressure.

The obtained liquid is added dropwise to methanol to precipitate asolid. The solid is dissolved in toluene and again added dropwise tomethanol to provide a precipitated solid that is filtered and dried,thereby obtaining Copolymer P-2 (0.63 g). The obtained copolymer ismeasured with respect to a weight average molecular weight andpolydispersity by SEC, Mw=52,300, and Mw/Mn=2.76.

Copolymer P-2 is assumed to have Structural Unit P-2 from an input ratioof the monomers.

Production of Quantum Dot Electroluminescence Device D-2

Quantum dot electroluminescence device D-2 is manufactured according tothe method as Example 1 except that Copolymer P-2 is used instead ofCopolymer P-1.

Example 3 Synthesis of Monomer M-3

Monomer M-3 is synthesized according to Reaction Scheme M-3.

2-(3-biphenylyl)amino-9,9-dimethyl fluorene (5.00 g),9-(4′bromo-[1,1′-biphenyl]-4-yl) 3,6-dichloro-9H-carbazole (12.9 g),palladium acetate (Pd(OAc)₂) (0.156 g), tri-tert-butylphosphoniumtetrafluoroborate (t-Bu₃P.BF₄) (0.150 g), sodium t-butoxide (2.65 g),and toluene (140 mL) are added a 500 mL four-necked flask, and stirredunder a nitrogen atmosphere at 100° C. for 5 hours.

An insoluble matter is filtered off with Celite®, and then activatedcarbon (5.0 g) and zeolite (5.0 g) are added to the filtrate, and themixture is stirred at 110° C. for 30 minutes. After filtering off aresulting solid with Celite®, the filtrate is passed through silica gel.The solvent is removed under a reduced pressure, and the residue ispurified by column chromatography (silica gel, hexane/toluene),obtainingN-([1,1′-biphenyl]-4-yl)-N-(4′-(3,6-dichloro-9H-carbazol-9-yl)-[1,1′-biphenyl]-4-yl)-9,9′-dimethyl-9H-fluorene-2-amine(9.18 g, Yield: 88.8%).

N-([1,1′-biphenyl]-4-yl)-N-(4′-(3,6-dichloro-9H-carbazol-9-yl)-[1,1′-biphenyl]-4-yl)-9,9′-dimethyl-9H-fluorene-2-amine(9.00 g), bis(pinacolato)diboron (7.64 g), potassium acetate (7.08 g),tris(dibenzylideneacetone) dipalladium (Pd₂(dba)₃) (0.551 g),2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl (XPhos) (0.860 g),and 1,4-dioxane (100 mL) are added to a 200 mL four-necked flask, andrefluxed under a nitrogen atmosphere for 4 hours.

The reaction solution is allowed to cool to room temperature, and asolid is filtered off with Celite®. The solvent is removed under areduced pressure, the residue is dissolved in toluene (100 mL), andactivated carbon (3 g) and zeolite (3 g) are added. The mixture isstirred at 130° C. for 30 minutes.

After filtering off a solid with Celite®, the filtrate is passed throughsilica gel. The toluene is removed under a reduced pressure, and theresidue is recrystallized with a mixed solvent of toluene and hexane anddried, thereby obtaining Monomer M-3 (6.94 g, Yield: 62.0%).

Synthesis of Copolymer P-3

Under a nitrogen atmosphere, Monomer M-3 (1.39 g),2,7-dibromo-9,9-dioctyl fluorene (0.824 g), palladium acetate (3.4 mg),tris(2-methoxy phenyl)phosphine (31.7 mg), toluene (44 mL), and a 20 wt% tetraethylammonium hydroxide aqueous solution (7.74 g) are added to afour-necked flask, and stirred at 85° C. for 6 hours. Subsequently,phenyl boronic acid (181 mg), bis(triphenylphosphine) palladium (II)dichloride (63.2 mg), and a 20 wt % tetraethylammonium hydroxide aqueoussolution (7.74 g) are added to the reaction flask, and the reactionmixture is stirred at 85° C. for 6 hours. Then, sodiumN,N-diethyldithiocarbamate trihydrate (5.07 g) dissolved in ionexchanged water (44 mL) is added to the reaction flask, and the mixtureis stirred at 85° C. for 2 hours.

After separating an organic layer from an aqueous layer, the organiclayer is washed with water, a 3 wt % acetic acid aqueous solution, andagain water. The organic layer is subject to column chromatographycharged with silica gel/alumina, and the solvent is removed from thecollected fractions under a reduced pressure. The obtained liquid isadded dropwise to methanol to form a precipitate. The precipitate isdissolved in toluene added dropwise to methanol to again form aprecipitate. The precipitated solid is filtered and dried, obtainingCopolymer P-3 (0.83 g). The copolymer is measured with respect to aweight average molecular weight and polydispersity by SEC, Mw=33,300,and Mw/Mn=2.19.

Copolymer P-3 is assumed to have Structural Unit P-3 from an input ratioof the monomers.

Production of Quantum Dot Electroluminescence Device D-3

Quantum dot electroluminescence device D-3 is manufactured according tothe same method as Example 1 except that Copolymer P-3 is used insteadof Copolymer P-1.

Example 4 Synthesis of Monomer M-4

Monomer M-4 is synthesized according to Reaction Scheme M-4.

2-(2-biphenylyl)amino-9,9-dimethyl fluorene (12.0 g),9-(4′bromo-[1,1′-biphenyl]-4-yl) 3,6-dichloro-9H-carbazole (15.5 g),palladium acetate (Pd(OAc)₂, 0.372 g), tri-tert-butylphosphoniumtetrafluoroborate (t-Bu₃P.BF₄, 0.722 g), sodium t-butoxide (6.38 g), andtoluene (330 mL) are added to a 500 mL four-necked flask, and stirredunder a nitrogen atmosphere at 100° C. for 1 hour. An insoluble matteris filtered off with Celite®, and activated carbon (6.0 g) and zeolite(6.0 g) are added to the filtrate, and mixture is stirred at 110° C. for30 minutes. After filtering a solid off with Celite®, the filtrate ispassed through silica gel. The toluene is removed under a reducedpressure, and the residue is purified by column chromatography (silicagel, hexane/toluene), obtainingN-([1,1′-biphenyl]-2-yl)-N-(4′-(3,6-dichloro-9H-carbazol-9-yl)-[1,1′-biphenyl]-4-yl)-9,9′-dimethyl-9H-fluorene-2-amine(18.2 g, Yield: 73.4%).

N-([1,1′-biphenyl]-2-yl)-N-(4′-(3,6-dichloro-9H-carbazol-9-yl)-[1,1′-biphenyl]-4-yl)-9,9′-dimethyl-9H-fluorene-2-amine(9.00 g), bis(pinacolato)diboron (7.64 g), potassium acetate (7.08 g),tris(dibenzylideneacetone) dipalladium (Pd₂(dba)₃) (0.551 g),2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl (XPhos) (0.860 g),and 1,4-dioxane (100 mL) are added to 200 mL four-necked flask, andrefluxed under a nitrogen atmosphere for 4 hours. The reaction solutionis allowed to cool to room temperature, and \ a solid is filtered offwith Celite®. The solvent is removed under a reduced pressure, and theresidue is dissolved in toluene (100 mL). Activated carbon (3 g) andzeolite (3 g) are added to the toluene solution and the mixture isstirred at 130° C. for 30 minutes. A solid is filtered off with Celite®,and the filtrate is passed through silica gel. The toluene is removedunder a reduced pressure, and the residue is recrystallized with a mixedsolvent of toluene and hexane and dried, thereby obtaining Monomer M-4(7.88 g, Yield: 63.5%).

Synthesis of Copolymer P-4

Under an argon atmosphere, Monomer M-4 (1.57 g),2,7-dibromo-9,9-di-n-octyl fluorene (0.927 g), palladium acetate (3.8mg), tris(2-methoxy phenyl)phosphine (30.9 mg), toluene (50 mL), and a20 wt % tetraethylammonium hydroxide aqueous solution (8.71 g) are addedto a four-necked flask, and stirred at 85° C. for 6 hours.

Subsequently, phenyl boronic acid (204 mg),dichlorobis(triphenylphosphine) palladium (71.1 mg), and a 20 wt %tetraethylammonium hydroxide aqueous solution (8.71 g) are added to thereaction flask, and the reaction mixture is stirred for 6 hours. Then,sodium N,N-diethyldithiocarbamate trihydrate (5.71 g) dissolved in ionexchanged water (50 mL) is added to the mixture, and stirred at 85° C.for 2 hours.

After separating an organic layer from an aqueous layer, the organiclayer is washed with water, a 3 wt % acetic acid aqueous solution, andagain water. The organic layer is subject to column chromatographycharged with silica gel/alumina, and the solvent is removed under areduced pressure. The obtained liquid is added dropwise to methanol toform a precipitate. The precipitate is dissolved in toluene and addeddropwise to methanol for precipitation. The precipitated solid isfiltered and dried, obtaining Copolymer P-4 (0.76 g). The copolymer ismeasured with respect to a weight average molecular weight andpolydispersity by SEC, Mw=72,700, and Mw/Mn=3.45.

Copolymer P-4 is assumed to have Structural Unit P-4 from an input ratioof the monomers.

Production of Quantum Dot Electroluminescence Device D-4

Quantum dot electroluminescence device D-4 is manufactured according tothe same method as Example 1 except that Copolymer P-4 is used insteadof Copolymer P-1.

Example 5 Synthesis of Copolymer P-5

Under an argon atmosphere, Monomer M-4 (1.42 g),2,7-dibromo-9,9-didodecylfluorene (1.01 g), palladium acetate (3.4 mg),tris(2-methoxy phenyl)phosphine (27.9 mg), toluene (50 mL), and a 20 wt% tetraethylammonium hydroxide aqueous solution (7.88 g) are added to afour-necked flask, and stirred at 85° C. for 6 hours. Subsequently,phenyl boronic acid (185 mg), dichlorobis(triphenylphosphine)palladium(64.4 mg), and a 20 wt % tetraethylammonium hydroxide aqueous solution(7.88 g) are added to the reaction flask, and the mixture is stirred at85° C. for another 6 hours. Then, sodium N,N-diethyldithiocarbamatetrihydrate (5.17 g) dissolved in ion exchanged water (50 mL) is added tothe reaction flask and the mixture is stirred at 85° C. for 2 hours.

After separating an organic layer from an aqueous layer, the organiclayer is washed with water, a 3 wt % acetic acid aqueous solution, andagain water. The organic layer is subjected to column chromatographycharged with silica gel/alumina, and the solvent is removed under areduced pressure. The obtained liquid is added dropwise to methanol toform a precipitate. The precipitate is dissolved in toluene, and againadded dropwise to methanol for precipitation. The precipitated solid isfiltered and dried, obtaining Copolymer P-5 (0.44 g). The copolymer ismeasured with respect to a weight average molecular weight andpolydispersity by SEC, Mw=30,000 and Mw/Mn=2.29.

Copolymer P-5 is assumed to have Structural Unit P-5 from an inputration of the monomers.

Production of Quantum Dot Electroluminescence Device D-5

Quantum dot electroluminescence device D-5 is manufactured according tothe same method as Example 1 except that Copolymer P-5 is used insteadof Copolymer P-1.

Example 6 Synthesis of Monomer M-5

Monomer M-5 is synthesized according to Reaction Scheme M-5.

3-chloro-9H-carbazole (10.0 g), 4-hexylbromobenzene (13.2 g), sodiumt-butoxide (t-BuONa) (7.15 g), tris(dibenzylideneacetone) dipalladium(Pd₂(dba)₃) (0.91 g), tri-tert-butylphosphonium tetrafluoroborate(t-Bu₃P.BF₄, 0.58 g), and toluene (169 mL) are added to a 500 mLfour-necked flask, and refluxed under a nitrogen atmosphere at 100° C.for 10 hours. The reaction solution is allowed to cool to roomtemperature, and the toluene is removed under a reduced pressure. Theresidue is purified by column chromatography (silica gel,hexane/toluene), obtaining 3-chloro-9-(4-hexylphenyl)-9H-carbazole (15.2g, Yield: 83%).

3-chloro-9-(4-hexylphenyl)-carbazole (15.0 g), bis(pinacolato)diboron(15.8 g), potassium acetate (5.97 g), tris(dibenzylideneacetone)dipalladium (Pd₂(dba)₃) (0.76 g),2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl (XPhos) (0.79 g),and 1,4-dioxane (145 mL) are added to a 500 mL four-necked flask, andrefluxed under a nitrogen atmosphere for 8 hours. The reaction solutionis allowed to cool to room temperature, and a solid is filtered off withCelite®. The solvent is removed under a reduced pressure, and theresidue is dissolved in toluene (50 mL). Activated carbon (1.5 g) andzeolite (1.5 g) are added to the toluene solution, and the mixturestirred at 130° C. for 30 minutes.

A solid is filtered off with Celite®, and the filtrate is passed throughsilica gel. The toluene is removed under a reduced pressure, and theresidue is recrystallized with a mixed solvent of toluene andacetonitrile and dried, thereby obtaining9-(4-hexylphenyl)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9H-carbazole(13.1 g, Yield: 70%). 3,6-dichloro-9H-carbazole (50.0 g),p-bromoiodobenzene (72.4 g), copper iodide (2.02 g), sodium t-butoxide(30.5 g), trans-1,2-cyclohexanediamine (2.42 g), and 1,4-dioxane (423mL) are added to a 1 L four-necked flask, and heated and stirred under anitrogen atmosphere at 100° C. for 12 hours.

The resulting mixture is allowed to cool to room temperature, and aninsoluble matter is filtered off with Celite®. The solvent is removedunder a reduced pressure, and the residue is dissolved in toluene (400mL). The solution is washed with water (500 mL), 2N—HCl (300 mL×2), andwater (300 mL×2) and dried with MgSO₄. The toluene is removed under areduced pressure, and the residue is recrystallized with a mixed solventof tetrahydrofuran/ethanol and dried, thereby obtaining9-(4-bromophenyl)-3,6-dichloro-9H-carbazole (56.6 g, Yield: 68.4%).

9-(4-hexylphenyl)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9H-carbazole)(10.0 g), 9-(4-bromophenyl)-3,6-dichloro-9H-carbazole (8.63 g), sodiumcarbonate (3.51 g), tetrakis(triphenylphosphine)palladium (Pd(PPh)₃)(1.27 g), toluene (45 mL), ethanol (55 mL), and distilled water (55 mL)are added to a 500 mL four-necked flask, and refluxed under a nitrogenatmosphere for 4 hours. The reaction solution is allowed to cool to roomtemperature, and a solid is filtered off with Celite®.

The filtrate is passed through silica gel, and the solvent is removedunder a reduced pressure. The residue is recrystallized with a mixedsolvent of toluene and methanol and dried, obtaining3,6-dichloro-9-(4-(9-(4-hexylphenyl)-9H-carbazol-3-yl)phenyl)-9H-carbazole(11.9 g, Yield: 84.4%).

3,6-dichloro-9-(4-(9-(4-hexylphenyl)-9H-carbazol-3-yl)phenyl)-9H-carbazole(10.0 g), bis(pinacolato)diboron (15.9 g), potassium acetate (9.04 g),palladium acetate (0.352 g),2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl (XPhos) (0.748 g),and 1,4-dioxane (157 mL) are added to a 500 mL four-necked flask, andrefluxed under a nitrogen atmosphere for 4 hours. The reaction solutionis allowed to cool to room temperature, and a solid is filtered off withCelite®. The solvent is removed under a reduced pressure, and theresidue is dissolved in toluene (200 mL). Activated carbon (3 g) andzeolite (3 g) are added to the toluene solution, and the mixture isstirred at 130° C. for 30 minutes.

A solid is filtered off with Celite®, and the filtrate is passed throughsilica gel. The toluene is removed under a reduced pressure, and theresidue is recrystallized with a mixed solvent of toluene andacetonitrile and dried, obtaining Monomer M-5 (7.68 g, Yield: 59.5%).

Synthesis of Copolymer P-6

Under an argon atmosphere, monomer M-5 (1.72 g), 2,7-dibromo-9,9-dioctylfluorene (1.152 g), palladium acetate (4.7 mg), tris(o-tolyl)phosphine(38.1 mg), toluene (57 mL), and a 20 wt % tetraethylammonium hydroxideaqueous solution (10.8 g) are added to a four-necked flask and then,stirred at 85° C. for 6 hours.

Subsequently, phenyl boronic acid (253 mg),dichlorobis(triphenylphosphine) palladium (88.0 mg), and a 20 wt %tetraethylammonium hydroxide aqueous solution (10.8 g) are added to thereaction flask, and stirred at 85° C. for 6 hours. Then, sodiumN,N-diethyldithiocarbamate trihydrate (7.06 g) dissolved in ionexchanged water (60 mL) is added to the reaction mixture, and themixture is stirred at 85° C. for 2 hours.

After separating an organic layer from an aqueous layer, the organiclayer is washed with water, a 3 wt % hydrochloric acid aqueous solution,and again water. The organic layer is subject to column chromatographycharged with silica gel/alumina, and the solvent is removed under areduced pressure. The obtained liquid is added dropwise to methanol toform a precipitate. The precipitated solid is dissolved in toluene andadded dropwise to methanol for precipitation. The precipitated solid isfiltered and dried, obtaining Copolymer P-6 (1.01 g). The copolymer ismeasured with respect to a weight average molecular weight andpolydispersity in SEC, Mw=16,500, and Mw/Mn=1.53.

Copolymer P-6 is assumed to have Structural Unit P-6 from an input ratioof the monomers.

Production of Quantum Dot Electroluminescence Device D-6

Quantum dot electroluminescence device D-6 is manufactured according tothe same method as Example 1 except that Copolymer P-6 is used insteadof Copolymer P-1.

Example 7 Synthesis of Monomer M-6

Monomer M-6 is synthesized according to Reaction Scheme M-6.

9,9′-spirobi[9H-fluorene]-2-amine (14.0 g), 1-bromobenzofuran (10.4 g),sodium t-butoxide (t-BuONa) (11.4 g), a [1,1′-bis(diphenylphosphino)ferrocene] palladium (II) dichloride dichloromethane adduct(PdCl₂(dppf) CH₂Cl₂) (1.71 g), and toluene (105 mL) are added to a 300mL four-necked flask and refluxed under a nitrogen atmosphere at 100° C.for 2 hours. The reaction solution is allowed to cool to roomtemperature, and toluene is removed under a reduced pressure. Theobtained solid is dispersed in methanol (400 mL), stirred for 1 hour,and then, filtered. The obtained solid is washed with water (300 mL) andmethanol (300 mL), recrystallized with a mixed solvent toluene andhexane, and dried, obtainingN-(9,9′-spirobi[fluorene]-2-yl)dibenzo[d,b]furan-1-amine (6.69 g, Yield:31.8%).

N-(9,9′-spirobi[fluorene]-2-yl) dibenzo[d,b]furan-1-amine (6.00 g),9-(4′bromo-[1,1′-biphenyl]-4-yl)3,6-dichloro-9H-carbazole (5.63 g),palladium acetate (Pd(OAc)₂) (0.135 g), tri-tert-butylphosphoniumtetrafluoroborate (t-Bu₃P.BF₄, 0.262 g), sodium t-butoxide (2.31 g), andtoluene (120 mL) are added to a 300 mL four-necked flask, and stirredunder a nitrogen atmosphere at 100° C. for 3 hours.

An insoluble matter is filtered off with Celite®, and activated carbon(3.0 g) and zeolite (3.0 g) are added to the filtrate, and stirred at110° C. for 30 minutes. A solid is filtered off with Celite®, and thefiltrate is passed through silica gel. The solvent is removed under areduced pressure, and the residue is purified by column chromatography(silica gel, hexane/toluene), thereby obtainingN-(9,9′-spirobi[fluorene]-2-yl)-N-(4′-(3,6-dichloro-9H-yl)-[1,1′-biphenyl]-4-yl)dibenzo[d,b]furan-1-amine) (7.40 g, Yield: 69.4%).

TheN-(9,9′-spirobi[fluorene]-2-yl)-N-(4′-(3,6-dichloro-9H-yl)-[1,1′-biphenyl]-4-yl)dibenzo[d,b]furan-1-amine)(5.00 g), bis(pinacolato)diboron (4.31 g), potassium acetate (3.33 g),tris(dibenzylideneacetone) dipalladium (Pd₂(dba)₃) (0.259 g),2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl (XPhos) (0.404 g),and 1,4-dioxane (45 mL) are added to a 200 mL four-necked flask, andrefluxed under a nitrogen atmosphere for 4 hours.

The reaction solution is allowed to cool to room temperature, and asolid is filtered off with Celite®. The solvent is removed under areduced pressure, and the residue is dissolved in toluene (100 mL).Activated carbon (3 g) and zeolite (3 g) are added to the toluenesolution, and the mixture is stirred at 130° C. for 30 minutes. A solidis filtered off with Celite®, and the filtrate is passed through silicagel. The toluene is removed under a reduced pressure, the residue isrecrystallized with a mixed solvent of toluene and acetonitrile anddried, obtaining Monomer M-6 (3.05 g, Yield: 50.5%).

Synthesis of Copolymer P-7

Under an argon atmosphere, Monomer M-6 (1.42 g), 2,7-dibromo-9,9-dioctylfluorene (0.822 g), palladium acetate (3.4 mg), tris(2-methoxyphenyl)phosphine (27.7 mg), toluene (55 mL), and a 20 wt %tetraethylammonium hydroxide aqueous solution (7.81 g) are added to afour-necked flask and stirred at 85° C. for 6 hours. Subsequently,phenyl boronic acid (183 mg), dichlorobis(triphenylphosphine)palladium(63.1 mg), and a 20 wt % tetraethylammonium hydroxide aqueous solution(7.81 g) are added to the reaction flask and stirred for 6 hours. Then,sodium N,N-diethyldithiocarbamate trihydrate (5.17 g) dissolved in ionexchanged water (50 mL) is added to the reaction mixture, and stirred at85° C. for 2 hours.

After separating an organic layer from an aqueous layer, the organiclayer is washed with water, a 3 wt % acetic acid aqueous solution, andagain water. The organic layer is subject to column chromatographyfilled with silica gel/alumina, and the solvent of the collectedfractions is removed under a reduced pressure. The obtained liquid isadded dropwise to methanol to form a precipitate. The precipitate isdissolved in toluene and added dropwise to methanol for precipitation,and the precipitated solid is filtered and dried, thereby obtainingCopolymer P-7 (0.81 g). The copolymer is measured with respect to aweight average molecular weight and polydispersity in SEC, Mw=69,900,and Mw/Mn=2.12.

Copolymer P-7 is assumed to have Structural Unit P-7 from an input ratioof the monomers.

Production of Quantum Dot Electroluminescence Device D-7

Quantum dot electroluminescence device D-7 is manufactured according tothe same method as Example 1 except that Copolymer P-7 is used insteadof Copolymer P-1.

Comparative Example 1 Production of Quantum Dot ElectroluminescenceDevice D-8

Quantum dot electroluminescence device D-8 is manufactured according tothe same method as Example 1 except that poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4′-(N-(4-sec-butyl phenyl)diphenyl amine)]having the following structural unit (TFB) (available from LuminescenceTechnology Corp.) is used instead of Copolymer P-1.

The weight average molecular weight (Mw) and polydispersity (Mw/Mn) ofTFB are measured by SEC. The weight average molecular weight (Mw) andthe polydispersity (Mw/Mn) of TFB are 359,000 and 3.40, respectively.

Comparative Example 2 Synthesis of Monomer M-7

Monomer M-7 is synthesized according to Reaction Scheme M-7.

9-[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-9H-carbazole(5.34 g), 4,4′-dibromo-4″-iodine triphenylamine (7.50 g), sodiumcarbonate (2.69 g), tetrakis(triphenylphosphine)palladium (0)(Pd(PPh₃)₄) (0.74 g), 1,4-dioxane (125 mL), and water (63 mL) are addedto a 500 mL 3-neck flask, and stirred under a nitrogen atmosphere at100° C. for 3 hours. The resultant is allowed to cool to roomtemperature, toluene (125 mL) is added and reaction mixture washed withwater (50 mL×3) and dried with MgSO₄.

The solvent is removed under a reduced pressure, and the residue isdissolved in toluene (50 mL) and hexane (100 mL). Activated carbon (8 g)is added to the toluene solution, and the mixture refluxed for 30minutes. The mixture is allowed to cool to room temperature, theactivated carbon (solids) is filtered off with Celite®, and the tolueneis removed under a reduced pressure. The residue is subject to columnchromatography and recrystallized (toluene/acetone), obtaining MonomerM-7 (6.38 g).

Synthesis of Copolymer P-8

Under an argon atmosphere, Monomer M-7 (1.47 g),2,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9,9-di-N-octylfluorene (1.47 g), palladium acetate (5.1 mg), tris (2-methoxyphenyl)phosphine (48.4 mg), toluene (59 mL), and a 20 wt %tetraethylammonium hydroxide aqueous solution (9.98 g) are added to afour-necked flask, and stirred at 85° C. for 6 hours. Subsequently,phenyl boronic acid (242 mg), tetrakis(triphenyl phosphino)palladium(52.9 mg), and a 20 wt % tetraethylammonium hydroxide aqueous solution(9.98 g) are added to the reaction flask, and stirred at 85° C. for 3hours. Then, sodium N,N-diethyldithiocarbamate trihydrate (7.74 g)dissolved in ion exchanged water (59 mL) is added to the reactionmixture, and stirred at 85° C. for 2 hours.

After separating an organic layer from an aqueous layer, the organiclayer is washed with water, a 3 wt % acetic acid aqueous solution, andagain water. The organic layer is subject to column chromatographyfilled with silica gel/alumina, and the solvent is removed under areduced pressure. The obtained liquid is added dropwise to methanol toform a precipitate. The precipitate is dissolved in toluene and addeddropwise to methanol for precipitation, and the precipitated solid isfiltered and dried, obtaining Copolymer P-8 (0.788 g). The obtainedcopolymer is measured with a weight average molecular weight andpolydispersity by SEC, Mw=74,000, and Mw/Mn=2.45.

Copolymer P-8 is assumed to have Structural unit P-8 from an input ratioof the monomers.

Production of Quantum Dot Electroluminescence Device D-9

Quantum dot electroluminescence device D-9 is manufactured according tothe same method as Example 1 except that Copolymer P-8 is used insteadof Copolymer P-1.

Evaluation Characteristics of Copolymers

Each copolymer according to the above examples and comparative examplesis measured with respect to a HOMO level (eV), a LUMO level (eV), and aglass transition temperature (Tg, ° C.). The results are shown in Table1.

Measurement of HOMO Level

Each example polymer is dissolved in xylene at a concentration of 1 wt %to provide a coating composition. The coating composition is spin-coatedat 2000 revolutions per minute (rpm) on a UV-cleaned and ITO-attachedglass substrate and dried on a hot plate at 150° C. for 30 minutes toprovide the test samples. The test samples are measured with respect toHOMO levels by using a photoelectron spectrometer (AC-3, Riken KeikiCo., Ltd.) in the air. The measurement results are used to calculate arising tangent point of intersection, which is regarded as the HOMOlevels (eV). The HOMO levels are usually a negative number.

Measurement of LUMO Level

Each example polymer is dissolved in toluene at a concentration of 3.2wt % to a coating composition. The coating composition is spin-coated at1600 rpm on a UV-cleaned and ITO-attached glass substrate and dried on ahot plate at 250° C. for 60 minutes to provide test samples (filmthickness: about 70 nm). The obtained test samples are cooled to 77K(−196° C.), and a photoluminescence (PL) spectra is obtained. The LUMOlevel (eV) is calculated from the peak value on the shortest wavelengthside of the PL spectrum.

Glass Transition Temperature (Tg)

The glass transition temperature (Tg, ° C.) of each example copolymer ismeasured by using differential scanning calorimetry (DSC) (Tradename:DSC6000, Seiko instruments Inc.) by increasing a temperature of a sampleup to 300° C. at 10° C./min, maintaining the temperature at 300° C. for10 minutes, decreasing the temperature down to 25° C. at 10° C./min,maintaining the temperature at 25° C. for 10 minutes, and then,increasing the temperature up to 300° C. at 10° C./min. When themeasurement procedure is completed, the sample is cooled down to roomtemperature (25° C.) at 10° C./min.

TABLE 1 Copol- Mw HOMO LUMO Tg ymer Structural unit (Mw/Mn) (eV) (eV) (°C.) Ex. 1 P-1

15,700 (1.60) 5.64 2.64 203 Ex. 2 P-2

52,300 (2.76) 5.72 2.69 205 Ex. 3 P-3

33,300 (2.19) 5.67 2.70 134 Ex. 4 P-4

72,700 (3.45) 5.71 2.63 207 Ex. 5 P-5

30,000 (2.29) 5.68 2.64 145 Ex. 6 P-6

16,500 (1.53) 5.60 2.54 148 Ex. 7 P-7

69,900 (2.12) 5.76 2.70 214 Comp. Ex. 1 TFB

359,000 (3.40) 5.54 2.60 156 Comp. Ex. 2 P-8

74,000 (2.45) 5.49 2.85 195

Evaluation of Quantum Dot Electroluminescence Device

Each quantum dot electroluminescence device is evaluated with respect toluminous efficiency and luminescence life-span in the following method.The results are shown in Table 2.

Luminous Efficiency

When a voltage is applied to each quantum dot electroluminescencedevice, a current starts to flow at a predetermined voltage, and thequantum dot electroluminescence device emits light. A DC constantvoltage power supply (a source meter, Keyence Corp.) is used togradually increase voltage, at which a current of each device ismeasured. A luminance measuring device (SR-3, Topcon Technology Co.,Ltd.) is used to measure luminance during the light emission. Themeasurement is completed when the luminance begins to decline. An areaof each device is used to calculate a current per unit area (currentdensity), and the luminance in candela per square meter (cd/m²) isdivided by the current density in amperes per square meter (A/m²) toobtain current efficiency, candela per ampere (cd/A).

Then, within the measured voltage range, the highest current efficiencyis obtained as “cd/A max”. The current efficiency represents efficiency(conversion efficiency) of converting a current into luminescent energyAccordingly, the greater current efficiency corresponds to a device thatexhibits higher performance.

In addition, when the DC constant voltage power supply (a source meter,Keyence Corp.) is used to apply a voltage to each quantum dotelectroluminescence device, a current begins to flow at a predeterminedvoltage, and the quantum dot electroluminescence device emits light. Avoltage (V) at the current density of 5 milliamperes per squarecentimeter (mA/cm²) is expressed as a driving voltage “V @5 mA”.Moreover, from a spectral radiation luminance spectrum measured by aluminance-measuring device, assuming that Lambertian radiation isperformed, external quantum efficiency (EQE) (%) at cd/A max iscalculated, which is also used to evaluate luminous efficiency.

Luminescence Life-Span

The DC constant voltage (a source meter, Keyence Corp.) is used to applya predetermined voltage to each quantum dot electroluminescence deviceresulting in light emission from the quantum dot electroluminescencedevice. The light emission of the quantum dot electroluminescence deviceis measured by using the luminance-measuring device (SR-3, TopconTechnology Co., Ltd.), as current is gradually increased and then ismade constant. When the luminance reached 650 nit (cd/m²), the device isleft alone.

The amount of time it takes for the measured luminance to graduallyreduce to 90% of the initial luminance is measured as “LT90 (hr)”.Likewise, the amount of time it takes for the measured luminance togradually reduce to 50% of the initial luminance is measured as “LT50(hr)”.

TABLE 2 V EQE LT90 cd/A max at 5 mA (%) (hr) LT50 (hr) Example 1 11.63.1 11.3 5.5 39.2 Example 2 10.5 3.0 10.4 9.3 63.0 Example 3 15.9 3.516.7 2.7 25.5 Example 4 13.4 3.3 14.3 4.1 79.1 Example 5 11.5 2.9 10.98.8 81.0 Example 6 10.2 3.0 9.7 9.9 80.4 Example 7 11.0 3.1 10.9 6.248.0 Comparative Example 1  8.4 4.3 9.2 0.6 12.0 Comparative Example 2 6.5 2.8 4.6 2.2 55.9

Referring to Table 2, the quantum dot electroluminescence devices of theexamples exhibit significantly high luminous efficiency and durability(particularly, luminescence life-span), compared with the quantum dotelectroluminescence devices of the comparative examples.

Moreover, although the present example embodiments are each highperforming blue quantum dot electroluminescence devices, similar resultsas indicated in Table 2 may be obtained with red quantum dotelectroluminescence devices and the like.

While this disclosure has been described in connection with what ispresently considered to be practical example embodiments, it is to beunderstood that the invention is not limited to the disclosedembodiments. On the contrary, it is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the appended claims.

DESCRIPTION OF SYMBOLS

-   -   100: electroluminescence device (EL device)    -   110: substrate    -   120: first electrode    -   130: hole injection layer    -   140: hole transport layer    -   150: light emitting layer    -   160: electron transport layer    -   170: electron injection layer    -   180: second electrode

What is claimed is:
 1. A copolymer comprising a structural unitrepresented by Chemical Formula 1:

wherein, in Chemical Formula 1, X is a single bond, -L_(1a)-, or-L_(1b)-L_(1c)-, wherein L_(1a), L_(1b), and L_(1c) are eachindependently a substituted or unsubstituted divalent aromatichydrocarbon group having 6 to 25 carbon atoms, L₂ is a substituted orunsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, ora substituted or unsubstituted aromatic heterocyclic group having 3 to25 ring-member atoms, Ar₁ and Ar₂ are each independently a substitutedor unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms,or a substituted or unsubstituted aromatic heterocyclic group having 3to 25 ring-member atoms, and Y is a substituted or unsubstituteddivalent aromatic hydrocarbon group having 6 to 60 carbon atoms, or asubstituted or unsubstituted divalent aromatic heterocyclic group having3 to 60 ring-member atoms, wherein, L₂, Ar₁, and Ar₂ satisfy at leastone of Conditions (i) or (ii): (i) Ar₁ and Ar₂ are different groups; and(ii) L₂ and Ar₁ join to form a ring.
 2. The copolymer of claim 1,wherein in Chemical Formula 1, L₂, Ar₁, and Ar₂ satisfy Condition (i),and Ar₁ and Ar₂ are each independently a group represented by ChemicalFormula 2A, Chemical Formula 2B, Chemical Formula 2C, or ChemicalFormula 2D:

wherein, in Chemical Formula 2A and Chemical Formula 2B R₁ and R₂ areeach independently hydrogen, a linear or branched hydrocarbon grouphaving 1 to 14 carbon atoms, an aromatic hydrocarbon group having 6 to14 carbon atoms, or an aromatic heterocyclic group having 3 to 25ring-member atoms, a and b are each independently an integer of 1 to 4,and a link without * indicates a bond to the nitrogen of the arylamineside chain of Chemical Formula 1

wherein, in Chemical Formula 2C and Chemical Formula 2D, Z₁ isCR_(a)R_(b), NR_(c), O, S, Se, or Te, wherein R_(a), R_(b), and R_(c)are each independently hydrogen, a linear or branched hydrocarbon grouphaving 1 to 14 carbon atoms, an aromatic hydrocarbon group having 6 to14 carbon atoms, or an aromatic heterocyclic group having 3 to 25ring-member atoms, or R_(a) and R_(b) are joined to provide a spirostructure, R₁, R₂, and R₃ are each independently hydrogen, a linear orbranched hydrocarbon group having 1 to 14 carbon atoms, an aromatichydrocarbon group having 6 to 14 carbon atoms, or an aromaticheterocyclic group having 3 to 25 ring-member atoms, a and b are eachindependently an integer of 1 to 4, and a link without * indicates abond to the nitrogen of the arylamine side chain of Chemical Formula 1.3. The copolymer of claim 1, wherein in Chemical Formula 1, L₂, Ar₁, andAr₂ satisfy Condition (i) and Ar₁ and Ar₂ are each a group representedby Group 2:

wherein, in Group 2, R is each independently a hydrogen atom or a linearor branched hydrocarbon group having 1 to 14 carbon atoms, a linkwithout * is a bond to the nitrogen of the arylamine side chain ofChemical Formula 1, and a hydrogen atom of an aromatic ring of a Group 2structure is optionally substituted by a linear or branched hydrocarbongroup having 1 to 14 carbon atoms.
 4. The copolymer of claim 1, whereinin Chemical Formula 1, L₂ is a group represented by Chemical Formula 3Aor Chemical Formula 3B:

wherein, in Chemical Formula 3A and Chemical Formula 3B, R₁ and R₂ areeach independently hydrogen, a linear or branched hydrocarbon grouphaving 1 to 14 carbon atoms, an aromatic hydrocarbon group having 6 to14 carbon atoms, or an aromatic heterocyclic group having 3 to 25ring-member atoms, a and b are each independently an integer of 1 to 4,and * indicates a linking portion with the bridge nitrogen of the mainchain carbazole ring of Chemical Formula 1, and a link without *indicates a bond to the nitrogen of the arylamine side chain of ChemicalFormula
 1. 5. The copolymer of claim 1, wherein in Chemical Formula 1,L₂ is represented by Chemical Formula 3A-1 or Chemical Formula 3B-1:

wherein, in Chemical Formula 3A-1 and Chemical Formula 3B-1, R₁ and R₂are each independently hydrogen, a linear or branched hydrocarbon grouphaving 1 to 14 carbon atoms, an aromatic hydrocarbon group having 6 to14 carbon atoms, or an aromatic heterocyclic group having 3 to 25ring-member atoms, a and b are each independently an integer of 1 to4, * indicates a linking portion with the bridge nitrogen of themainchain carbazole ring of Chemical Formula 1, and a link without *indicates a bond to the nitrogen of the arylamine side chain of ChemicalFormula
 1. 6. The copolymer of claim 1, wherein in Chemical Formula 1,L₂ is a group represented by Group 3:

wherein, in Group 3, * indicates a linking portion with the bridgenitrogen of the main chain carbazole ring of Chemical Formula 1, and alink without * indicates a bond to the nitrogen of the arylamine sidechain of Chemical Formula
 1. 7. The copolymer of claim 1, wherein inChemical Formula 1, L₂, Ar₁, and Ar₂ satisfy Condition (ii), and-L₂-N(Ar₁)(Ar₂) is a group represented by Chemical Formula 4A orChemical Formula 4B:

wherein, in Chemical Formula 4A and Chemical Formula 4B, R₁ and R₂ areeach independently hydrogen, a linear or branched hydrocarbon grouphaving 1 to 14 carbon atoms, an aromatic hydrocarbon group having 6 to14 carbon atoms, or an aromatic heterocyclic group having 3 to 25ring-member atoms, a and b are each independently an integer of 1 to4, * indicates a linking portion with the bridge nitrogen of the mainchain carbazole ring of Chemical Formula 1, Cy is a substituted orunsubstituted N-containing heterocyclic ring group having 5 to 25ring-member atoms, and Ar₂ is defined as in Chemical Formula
 1. 8. Thecopolymer of claim 1, wherein in Chemical Formula 1, L₂, Ar₁, and Ar₂satisfy Condition (ii), and -L₂-N(Ar₁)(Ar₂) is a group represented byGroup 4:

wherein, in Group 4, Ar₂ is as defined as in Chemical Formula 1, *indicates a linking portion with the bridge nitrogen of the main chaincarbazole ring of Chemical Formula 1, and a hydrogen atom of an aromaticring of a Group 4 structure is optionally substituted by a linear orbranched hydrocarbon group having 1 to 14 carbon atoms.
 9. The copolymerof claim 7, wherein in Chemical Formula 1, Ar₂ is represented by one ofChemical Formula 2A, Chemical Formula 2B, Chemical Formula 2C, orChemical Formula 2D:

wherein, in Chemical Formula 2A and Chemical Formula 2B R₁ and R₂ areeach independently hydrogen, a linear or branched hydrocarbon grouphaving 1 to 14 carbon atoms, an aromatic hydrocarbon group having 6 to14 carbon atoms, or an aromatic heterocyclic group having 3 to 25ring-member atoms, a and b are each independently an integer of 1 to 4,and a link without * is a bond to the nitrogen of the arylamine sidechain of Chemical Formula 1,

wherein, in Chemical Formula 2C and Chemical Formula 2D, Z₁ isCR_(a)R_(b), NR_(c), O, S, Se, or Te, wherein R_(a), R_(b), and R_(c)are each independently hydrogen, a linear or branched hydrocarbon grouphaving 1 to 14 carbon atoms, an aromatic hydrocarbon group having 6 to14 carbon atoms, or an aromatic heterocyclic group having 3 to 25ring-member atoms, or R_(a) and R_(b) are joined to provide a spirostructure, R₁, R₂, and R₃ are each independently hydrogen, a linear orbranched hydrocarbon group having 1 to 14 carbon atoms, an aromatichydrocarbon group having 6 to 14 carbon atoms, or an aromaticheterocyclic group having 3 to 25 ring-member atoms, a and b are eachindependently an integer of 1 to 4, and a link without * indicates abond to the nitrogen of an arylamine side chain of Chemical Formula 1.10. The copolymer of claim 7, wherein in Chemical Formula 1, Ar₂ is agroup represented by Group 2:

wherein, in Group 2, R is each independently a hydrogen atom or a linearor branched hydrocarbon group having 1 to 14 carbon atoms, a linkwithout * is a bond to the nitrogen of an arylamine side chain ofChemical Formula 1, and a hydrogen atom of the aromatic ring of a Group2 structure is optionally substituted by a linear or branchedhydrocarbon group having 1 to 14 carbon atoms.
 11. The copolymer ofclaim 1, wherein in Chemical Formula 1, Y is represented by one ofChemical Formula 5A, Chemical Formula 5B, Chemical Formula 5C, ChemicalFormula 5D, or Chemical Formula 5E:

wherein, in Chemical Formula 5A, R₁ is each independently hydrogen, alinear or branched hydrocarbon group having 1 to 14 carbon atoms, anaromatic hydrocarbon group having 6 to 14 carbon atoms, or an aromaticheterocyclic group having 3 to 25 ring-member atoms, a is an integer of1 to 4, and Chemical Formula 5B

wherein, in Chemical Formula 5B and Chemical Formula 5C, Z₁ isCR_(a)R_(b), NR_(c), O, S, Se, or Te, wherein R_(a), R_(b), and R_(c)are each independently hydrogen, linear or branched hydrocarbon grouphaving 1 to 14 carbon atoms, an aromatic hydrocarbon group having 6 to14 carbon atoms, or an aromatic heterocyclic group having 3 to 25ring-member atoms, or R_(a) and R_(b) are linked to each other toprovide a spiro structure, R₁, R₂, R₃, and R₄ are each independentlyhydrogen, a linear or branched hydrocarbon group having 1 to 14 carbonatoms, an aromatic hydrocarbon group having 6 to 14 carbon atoms, or anaromatic heterocyclic group having 3 to 25 ring-member atoms, a and bare each independently an integer of 1 to 3, and c and d are eachindependently an integer of 1 to 3,

wherein, in Chemical Formula 5D and Chemical Formula 5E, R₁, R₂, R₃, R₄,and R₅ are each independently hydrogen, a linear or branched hydrocarbongroup having 1 to 14 carbon atoms, an aromatic hydrocarbon group having6 to 14 carbon atoms, or an aromatic heterocyclic group having 3 to 25ring-member atoms, and a, b, c, d, and e are each independently aninteger of 1 to
 4. 12. The copolymer of claim 1, wherein in ChemicalFormula 1, Y is a group represented by Group 5:

wherein, in Group 5, R₁, R₂, and R₄ are each independently hydrogen, alinear or branched hydrocarbon group having 1 to 14 carbon atoms, or aC6 to C25 aromatic hydrocarbon group, and R₃ is each independently alinear or branched hydrocarbon group having 1 to 14 carbon atoms. 13.The copolymer of claim 12, wherein in Chemical Formula 1, Y includes agroup represented by at least one of the Groups (5-1) to (5-7).
 14. Aliquid composition, comprising the copolymer of claim 1 and a solvent ora dispersive medium.
 15. A thin film comprising the copolymer ofclaim
 1. 16. An electroluminescence device material comprising thecopolymer of claim
 1. 17. An electroluminescence device, comprising afirst electrode and a second electrode, and at least one organic layerbetween the first electrode and the second electrode, wherein at leastone layer of the organic layer comprises the copolymer of claim
 1. 18.The electroluminescence device of claim 17, wherein the organic layercomprising the copolymer is a hole transport layer or a hole injectionlayer.
 19. The electroluminescence device of claim 17, wherein theorganic layer comprises a light emitting layer comprising semiconductornanoparticles or an organometallic complex.
 20. The electroluminescencedevice of claim 17, wherein at least one layer of the organic layer isformed by a coating method.